KR102427687B1 - Compound, resin, resist composition and method for producing resist pattern - Google Patents

Abstract

식 중, R¹은 C₁ 내지 C₈의 불소화 알킬기를 나타내고, R²는 치환기를 갖고 있어도 되는 C₅ 내지 C₁₈의 지환식 탄화수소기를 가지는 기를 나타내고, *은 결합손을 나타낸다.A compound having a group represented by the formula (I a):

In the formula, R ¹ represents a C ₁ to C ₈ fluorinated alkyl group, R ² represents a group having an optionally substituted C ₅ to C ₁₈ alicyclic hydrocarbon group, and * represents a bond.

Description

A compound, a resin, a resist composition, and the manufacturing method of a resist pattern TECHNICAL FIELD

Cross-referencing of related applications

This application claims priority to Japanese Patent Application JP2014-170797 filed on August 25, 2014. The entire specification of Japanese patent application JP2014-170797 is hereby incorporated by reference.

background of the invention

1. Field of invention

The present invention relates to a compound, a resin, a resist composition, and a method for producing a resist pattern.

2. Prior art

A resist composition comprising a resin comprising a structural unit derived from a compound represented by the following formula is described in the specification of JP2013-040319A.

Summary of the invention

The present invention provides the following inventions <1> to <9>.

<1> A compound having a group represented by formula (Ia).

Here, R ¹ represents a C ₁ to C ₈ fluorinated alkyl group,

R ² represents a group having an optionally substituted C ₅ to C ₁₈ alicyclic hydrocarbon group,

* indicates a bond.

<2> The compound according to <1>,

The alicyclic hydrocarbon group is an unsubstituted alicyclic hydrocarbon group.

<3> The compound according to <1> or <2>,

It is a compound represented by formula (I),

where R ¹ and R ² are defined above,

R ³ represents a C ₁ to C ₆ alkyl group which may have a hydrogen atom, a halogen atom or a fluorine atom.

A ¹ represents a single bond or an optionally substituted C ₁ to C ₁₀ saturated hydrocarbon group, and the methylene group contained in the saturated hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.

<4> The compound according to any one of <1> to <3>,

R ² is a cyclohexyl group, a cyclopentyl group, a norbornyl group, or an adamantyl group.

<5> A resin having a structural unit derived from the compound according to any one of <1> to <4>.

<6> The resin according to <5>,

Resin which contains 50 mol% or more of structural units derived from the compound which has group represented by Formula (Ia).

<7> The resin according to <5> or <6>,

Resin comprised by the structural unit derived from the compound which has group represented by Formula (Ia).

<8> A resist composition, comprising:

The resin according to any one of <5> to <7>,

a resin having an acid labile group, and

A resist composition comprising an acid generator.

<9> A method for producing a resist pattern comprising steps (1) to (5):

(1) a step of applying the resist composition according to <8> on a substrate;

(2) drying the applied composition to form a composition layer;

(3) a step of exposing the composition layer;

(4) heating the exposed composition layer; and

(5) A step of developing the heated composition layer.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

"(meth)acrylic monomer" means a monomer having a structure of "CH ₂ =CH-CO-" or "CH ₂ =C(CH ₃ )-CO-", and similarly "(meth)acrylate" and "(meth)acrylic acid" means "acrylate or methacrylate" and "acrylic acid or methacrylic acid", respectively. Here, the chain structure groups include a group having a straight-chain structure and a group having a branched structure. The indefinite articles “a” and “an” have the same meaning as “one or more”.

In the present specification, the term "solid content" means components other than the solvent from the resist composition.

<A compound having a group represented by formula (Ia)>

The compounds of the present invention have a group represented by the formula (Ia), which is sometimes referred to as "group (Ia)".

Here, R ¹ represents a C ₁ to C ₈ fluorinated alkyl group,

R ² represents a group having an optionally substituted C ₅ to C ₁₈ alicyclic hydrocarbon group,

* indicates a bond.

Examples of the fluorinated alkyl group include a difluoromethyl group, a trifluoromethyl group, a 1,1-difluoroethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, a perfluoroethyl group, 1,1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1-(trifluoromethyl)-1,2 , 2,2-tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1, 1,2,2,3,3,4,4-octafluorobutyl group, 3-(trifluoromethyl)-2,2,3,4,4,4-hexafluorobutyl group, perfluoro Butyl group, 1,1-bis(trifluoromethyl)-2,2,2-trifluoroethyl group, 2-(perfluoropropyl)ethyl group, 1,1,2,2,3,3,4, 4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl group, 1,1-bis(trifluoromethyl )-2,2,3,3,3-pentafluoropropyl group, perfluoropentyl group, 2-(perfluorobutyl)ethyl group, 1,1,2,2,3,3,4,4, 5,5-decafluorohexyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, perfluoropentylmethyl group and perfluoro contains a hexyl group.

R ¹ is preferably a C ₂ to C ₅ fluorinated alkyl group having one methylene group or a C ₁ to C ₄ perfluoroalkyl group, more preferably a single methylene group, trifluoromethyl group, perfluoro A C ₂ to C ₅ fluorinated alkyl group having a roethyl group, more preferably a trifluoromethyl group, a perfluoroethyl group, or 3-(trifluoromethyl)-2,2,3,4,4,4 -It is a hexafluorobutyl group.

Examples of the C ₅ to C ₁₈ alicyclic hydrocarbon group for R ² include a cycloalkyl group, for example, a monocyclic group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and a polycyclic hydrocarbon group such as a decahydronaphthyl group, an adamantyl group, and a norbornyl group.

The alicyclic hydrocarbon group is preferably a C ₅ to C ₈ cycloalkyl group or a C ₈ to C ₁₀ polycyclic hydrocarbon group, more preferably a cyclohexyl group, a cyclopentyl group, a norbornyl group or an adamantyl group. , more preferably a cyclopentyl group or a cyclohexyl group, and further more preferably a cyclohexyl group.

Examples of the substituent of the alicyclic hydrocarbon group for R ² are a halogen atom, a C ₁ to C ₆ alkyl group, a C ₃ to C ₁₆ monovalent alicyclic hydrocarbon group, a C ₁ to C ₁₂ alkoxy group, C ₆ to It includes a C ₁₈ monovalent aromatic hydrocarbon group, a C ₇ to C ₂₁ aralkyl group, and a C ₂ to C ₄ acyl group.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of the alkyl group include a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group and n-hexyl group.

Examples of the alicyclic hydrocarbon group include a cycloalkyl group, for example, a monocyclic group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and decahydronaphthyl group, adamantyl group, norbornyl group, and polycyclic hydrocarbon groups such as the following groups. * indicates a bond.

Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group and a dodecyloxy group.

Examples of the monovalent aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, and an aryl group such as a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, a diethylphenyl group, and a 2-methyl-6-ethylphenyl group.

Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group and a naphthylethyl group.

Examples of the acyl group include an acetyl group, a propionyl group and a butyryl group.

The alicyclic hydrocarbon group for R ² is preferably an unsubstituted C ₅ to C ₁₈ alicyclic hydrocarbon group.

R ² may be composed of an alicyclic hydrocarbon group and an alicyclic hydrocarbon group including a divalent group such as a C ₁ to C ₆ alkanediyl group, a carbonyloxy group, or an oxycarbonyl group. R ² is preferably a group composed of an alicyclic hydrocarbon group, for example, a group having only one alicyclic hydrocarbon group.

The compound having the group (Ia) preferably further has a polymerizable group. Examples of the polymerizable group include a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group or a methacryloylamino group.

The compound having the group (Ia) preferably has a structure represented by formula (I0).

Here, R ³ represents a C ₁ to C ₆ alkyl group which may have a hydrogen atom, a halogen atom, or a fluorine atom.

A ¹ represents a single bond or an optionally substituted C ₁ to C ₁₀ saturated hydrocarbon group, and the methylene group contained in the saturated hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.

X represents an oxygen atom or an NH group.

* indicates a bond with the group (Ia).

Examples of the alkyl group of R ³ include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group and n-hexyl group. The alkyl group, preferably a C ₁ to C ₄ alkyl group, more preferably a methyl group and an ethyl group.

Examples of the halogen atom of R ³ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of the alkyl group having a halogen atom for R ³ are trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorosec-butyl group, purple Luoro includes a tert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a perchloromethyl group, a perbromomethyl group and a periodomethyl group.

R ³ is preferably a hydrogen atom or a methyl group.

Examples of the C ₁ to C ₁₀ saturated hydrocarbon group of A ¹ are an alkanediyl group or a divalent alicyclic hydrocarbon group, and the alkanediyl group and the methylene group included in the saturated hydrocarbon group may be substituted with an oxygen atom or a carbonyl group do.

Examples of the alkanediyl group include a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, and a hexane-1,6-diyl group. , a linear alkanediyl group; and

A group in which a linear alkanediyl group is bonded to a side chain of a C ₁ to C ₄ alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, or a tert-butyl group, for example, butane -1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group and 2-methylbutane-1,4- and a branched alkanediyl group which is a diyl group.

Examples of the alicyclic hydrocarbon group include a cyclopentanediyl group, a cyclohexanediyl group, an adamantanediyl group, and a norbornanediyl group. Among these, a cyclohexanediyl group and an adamantanediyl group are preferable, and an adamantanediyl group is more preferable.

Examples of the alkanediyl group in which the methylene group is substituted with an oxygen atom or a carbonyl group include a group represented by ^* -A ² -X ¹ -(A ³ -X ² ) _a -, A ² and A ³ are each independently C ₁ To C ₆ Represents an alkanediyl group, X ¹ And X ² Each independently represents -O-, -CO-O- or -O-CO-, "a" represents 0 or 1, provided that A ² and A ³ have a total of 10 or less carbon atoms, and * represents a bond bonded to an oxygen atom.

^* Examples of -A ² -X ¹ -(A ³ -X ² ) _a - are, ^* -A ² -O-, ^* -A ² -CO-O-, ^* -A ² -O-CO-, ^* -A ² -CO-OA ³ -CO-O-, ^* -A ² -O-CO-A ³ -O-, ^* -A ² -OA ³ -CO-O-, ^* -A ² -CO-OA ³ -O-CO-, and ^* -A ² -O-CO-A ³ -O-CO-. Among them, ^* -A ² -O-, ^* -A ² -CO-O-, ^* -A ² -CO-OA ³ -CO-O- or ^* -A ² -OA ³ -CO-O- are preferable. do.

A ¹ Preferably it is a single bond, a methylene group, or an ethylene group, More preferably, it is a methylene group.

Examples of the structure represented by the formula (IO) include the following. In each structure, * represents a bond with the group (Ia). t represents the integer of 1-6.

It is preferable that the compound which has group (Ia) is a compound represented by Formula (I). This compound is sometimes referred to as “Compound (I)”.

Here, R ¹ , R ² , R ³ and A ¹ are defined above.

Examples of the compound having the group (Ia) include the following compounds.

Further, examples of compound (I) include structural units in which the methyl group corresponding to R ³ in the compound represented as above is substituted with a hydrogen atom.

<Method for preparing compound having group (Ia)>

A compound having a group (Ia), for example, compound (I), is prepared by reacting a compound represented by formula (I-a) with a compound represented by formula (I-b) in a solvent in the presence of a catalyst. can do.

wherein R ¹ , R ² , R ³ and A ¹ are defined above.

Preferred examples of the solvent include chloroform, tetrahydrofuran and toluene.

Preferred examples of the catalyst include a base catalyst such as dimethylaminopyridine and pyridine, or a known esterification catalyst such as an acid catalyst or a carbodiimide catalyst. The base catalyst and the known esterification catalyst are used together for the reaction.

Preferred examples of the compound represented by the formula (I-a) include the following, which are readily available in the market.

Preferred examples of the compound represented by the formula (I-b) include the compound represented by the following formula, which is readily available in the market.

Preferred examples of the carbodiimide catalyst include a salt represented by the following formula, which is readily available in the market.

<Resin Containing Structural Units Derived from Compounds Having Group (Ia)>

The resin of the present invention comprises a structural unit derived from a compound comprising a group (Ia), which is a resin having a group (Ia) (which is sometimes referred to as “resin (X)”).

Resin (X) is a structural unit having an acid labile group (which is sometimes referred to as "structural unit (a1)"), a structural unit having no acid labile group, and a known structural unit other than the structural units mentioned above. The said resin (X), Preferably, a structural unit (a1) is not included.

In the resin (X), the content of the structural unit (Ia) is preferably 10 to 100 mol%, more preferably 50 to 100 mol%, based on the total (100 mol%) of all structural units of the resin (X). It is 100 mol%, More preferably, it is 80-100 mol%, Especially preferably, it is 100 mol%.

The weight average molecular weight of the resin (X) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less).

The weight average molecular weight is a value measured by gel permeation chromatography using polystyrene as a standard product. The detailed conditions of this assay are described in the Examples.

<Resist composition>

The resist composition of the present invention comprises:

resin (X),

a resin having an acid labile group (which is sometimes referred to as "resin (A)"), and

acid generator (which is sometimes referred to as "acid generator (B)").

The "acid labile group" herein means a group having a leaving group which leaves by contact with an acid to form a hydrophilic group such as a hydroxy group or a carboxy group.

The resist composition preferably further comprises a material (which is sometimes referred to as "container (C)"). The resist composition preferably further comprises a solvent (which is sometimes referred to as "solvent (E)").

The resist composition of the present invention preferably further comprises a salt having a weak acidity, such as a salt in a weak acid molecule (which is sometimes referred to as "salt in a weak acid molecule (D)"), such as in (C). do.

< Resin (A) >

Resin (A) contains a structural unit having an acid labile group (which is sometimes referred to as "structural unit (a1)"). The resin (A) may further preferably contain structural units other than the structural unit (a1). Examples of the structural unit other than the structural unit (a1) include a structural unit having no acid labile group (which is sometimes referred to as "structural unit (s)").

<Structural unit (a1)>

The structural unit (a1) is derived from a monomer having an acid labile group (which is sometimes referred to as "monomer (a1)").

In the resin (A), the acid-labile group contained in the structural unit (a1) is preferably the following group (1) and/or group (2).

wherein, R ^a1 to R ^a3 each independently represent a C ₁ to C ₈ alkyl group, a C ₃ to C ₂₀ alicyclic hydrocarbon group, or a combination thereof, or R ^a1 and R ^a2 are bonded to them It can be combined with a carbon atom to form a C ₃ to C ₂₀ divalent alicyclic hydrocarbon group,

na represents an integer of 0 or 1,

* indicates a bond.

Here, R ^a1′ and R ^a2′ each independently represent a hydrogen atom or a C ₁ to C ₁₂ hydrocarbon group, and R ^a3′ represents a C ₁ to C ₂₀ hydrocarbon group, or R ^a2′ and R ^a3′ may combine with the carbon atom and X bonded thereto to form a divalent C ₃ to C ₂₀ heterocyclic group, and the methylene group included in the hydrocarbon group or the divalent heterocyclic group is substituted with an oxygen atom or a sulfur atom may be,

X represents -O- or -S-,

* indicates a bond.

Examples of the alkyl group of R ^a1 to R ^a3 include a methyl group, an ethyl group, a propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, and n-octyl group.

Examples of the alicyclic hydrocarbon group of R ^a1 to R ^a3 include a cycloalkyl group, for example, a monocyclic group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and decahydronaphthyl group, adamantyl group, norbornyl group, and polycyclic hydrocarbon groups such as the following groups. * indicates a bond.

The alicyclic hydrocarbon group of R ^a1 to R ^a3 preferably has 3 to 16 carbon atoms.

Examples of the group combining an alkyl group and an alicyclic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, and a norbornylethyl group.

na is preferably an integer of 0.

When R ^a1 and R ^a2 combine together to form a divalent alicyclic hydrocarbon group, examples of the -C(R ^a1 )(R ^a2 )(R ^a3 ) group include the following groups. The divalent alicyclic hydrocarbon group preferably has 3 to 12 carbon atoms. * represents a bond with -O-.

Specific examples of the group represented by formula (1) are, for example,

1,1-dialkylalkoxycarbonyl group (in formula (1), R ^a1 to R ^a3 are an alkyl group, preferably a tert-butoxycarbonyl group);

2-alkyladamantan-2-yloxycarbonyl group (in formula (1), R ^a1 , R ^a2 and a carbon atom form an adamantyl group, and R ^a3 is an alkyl group), and

1-(adamantan-1-yl)-1-alkylalkoxycarbonyl group (in formula (1), R ^a1 and R ^a2 are alkyl groups and R ^a3 is adamantyl group).

The hydrocarbon group of R ^a1' to R ^a3' includes any of an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining them.

Examples of the alkyl group and the alicyclic hydrocarbon group are the same as the above examples.

Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, and a biphenyl group. , a phenanthryl group, a 2,6-diethylphenyl group, an aryl group such as 2-methyl-6-ethylphenyl.

Examples of the divalent heterocyclic group formed by bonding R ^a2′ and R ^a3′ to each other include the following groups.

At least one of R ^a1' and R ^a2' is preferably a hydrogen atom.

Specific examples of the group represented by formula (2) include the following groups. * indicates a bond.

The monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond, and more preferably a (meth)acrylic monomer having an acid labile group.

Among the (meth)acrylic monomers having an acid-labile group, a monomer having a C ₅ to C ₂₀ alicyclic hydrocarbon group is preferable. When a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in a resist composition, a resist composition having excellent resolution tends to be obtained.

Examples of the structural unit derived from the (meth)acrylic monomer having a group represented by the formula (1) are preferably represented by the following formulas (a1-0), (a1-1) and (a1-2) contains structural units. These may be used as a single structural unit or may be used as a combination of two or more types of structural units. The structural unit represented by the formula (a1-0), the structural unit represented by the formula (a1-1), and the structural unit represented by the formula (a1-2) are sometimes referred to as "structural unit (a1-0)", " The monomers from which the structural unit (a1-1)" and the "structural unit (a1-2)" are referred to as the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2) are , sometimes referred to as "monomer (a1-0)", "monomer (a1-1)" and "monomer (a1-2)", respectively,

Here, L ^a01 represents -O- or ^* -O-(CH ₂ ) _k01 -CO-O-,

k01 represents an integer of 1 to 7,

* represents a bond with -CO-,

R ^a01 represents a hydrogen atom or a methyl group, and

R ^a02 , R ^a03 and R ^a04 each independently represent a C ₁ to C ₈ alkyl group, a C ₃ to C ₁₈ alicyclic hydrocarbon group, or a combination thereof.

L ^a01 is preferably -O- or ^* -O-(CH ₂ ) _k01 -CO-O-, more preferably -O-, k01 is preferably an integer of 1 to 4, more preferably It is usually an integer of 1.

Examples of the alkyl group and the alicyclic hydrocarbon group of R ^a02 , R ^a03 and R ^a04 and combinations thereof are the same as the examples of the group described for R ^a1 to R ^a3 in Formula (1).

The alkyl group of R ^a02 , R ^a03 and R ^a04 is preferably a C ₁ to C ₆ alkyl group.

The alicyclic hydrocarbon group of R ^a02 , R ^a03 and R ^a04 is preferably a C ₃ to C ₈ alicyclic hydrocarbon group, more preferably a C ₃ to C ₆ alicyclic hydrocarbon group.

The group combining an alkyl group and an alicyclic hydrocarbon group preferably has 18 or less carbon atoms. Examples of such a group include a methylcyclohexyl group, a dimethylcyclohexyl group, and a methylnorbornyl group.

R ^a02 and R ^a03 are preferably a C ₁ to C ₆ alkyl group, more preferably a methyl group or an ethyl group.

R ^a04 is preferably a C ₁ to C ₆ alkyl group or a C ₅ to C ₁₂ alicyclic hydrocarbon group, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group.

Here, L ^a1 and L ^a2 each independently represent -O- or ^* -O-(CH ₂ ) _k1 -CO-O-,

k1 represents an integer of 1 to 7,

* represents a bond with -CO-,

R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group,

R ^a6 and R ^a7 each independently represent a group that is a C ₁ to C ₈ alkyl group, a C ₃ to C ₁₈ alicyclic hydrocarbon group, or a combination thereof,

m1 represents an integer from 0 to 14,

n1 represents an integer from 0 to 10, and

n1' represents the integer of 0-3.

L ^a1 and L ^a2 are preferably -O- or ^* -O-(CH ₂ ) _k1' -CO-O-, more preferably -O-, k1' is preferably an integer of 1 to 4 , more preferably 1.

R ^a4 and R ^a5 are preferably a methyl group.

Examples of the alkyl group of R ^a6 and R ^a7 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n - Includes a heptyl group, a 2-ethylhexyl group, and an n-octyl group.

Examples of the alicyclic hydrocarbon group of R ^a6 and R ^a7 include a cycloalkyl group, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group. , a monocyclic hydrocarbon group such as a cyclooctyl group, a cycloheptyl group, and a cyclodecyl group; and decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1-(adamantan-1-yl)alkan-1-yl group, norbornyl group, methylnorbornyl group and isobornyl group and polycyclic hydrocarbon groups such as the group.

Examples of the group formed by combining the alkyl group and the alicyclic hydrocarbon group of R ^a6 and R ^a7 include an aralkyl group such as a benzyl group and a phenethyl group.

The alkyl group of R ^a6 and R ^a7 is preferably a C ₁ to C ₆ alkyl group.

The alicyclic hydrocarbon group of R ^a6 and R ^a7 is preferably a C ₃ to C ₈ alicyclic hydrocarbon group, more preferably a C ₃ to C ₆ alicyclic hydrocarbon group.

m1 is preferably an integer of 0 to 3, more preferably 0 or 1.

n1 is preferably an integer of 0 to 3, more preferably 0 or 1.

n1' is preferably 0 or 1, more preferably 1.

Examples of the monomer (a1-0) preferably include monomers represented by the following formulas (a1-0-1) to (a1-0-12), more preferably the following formulas (a1-0-) 1) to the monomers represented by formulas (a1-0-10) are included.

Examples of the structural unit (a1-0) above include a structural unit in which a methyl group corresponding to R ^a01 in the structural unit represented as above is substituted with a hydrogen atom.

Examples of the monomer (a1-1) include the monomer described in Japanese Patent Application Laid-Open No. 2010-204646. Among these, the monomer is preferably a monomer represented by formulas (a1-1-1) to (a1-1-8), more preferably formulas (a1-1-1) to (a1-1-4) ) as a monomer.

Examples of the monomer (a1-2) include 1-methylcyclopentan-1-yl (meth)acrylate, 1-ethylcyclopentan-1-yl (meth)acrylate, 1-methylcyclohexan-1-yl ( meth)acrylate, 1-ethylcyclohexan-1-yl (meth)acrylate, 1-ethylcycloheptan-1-yl (meth)acrylate, 1-ethylcyclooctan-1-yl (meth)acrylate; 1-isopropylcyclopentan-1-yl (meth)acrylate, and 1-isopropylcyclohexan-1-yl (meth)acrylate. Among these, the monomer is preferably a monomer represented by the following formulas (a1-2-1) to (a1-2-12), more preferably the formulas (a1-2-3), (a1-2- 4), a monomer represented by the formula (a1-2-9) or (a1-2-10), more preferably a monomer represented by the formulas (a1-2-3) and (a1-2-9) It is a monomer.

When the resin (A) contains the structural unit (a1-0) and/or the structural unit (a1-1) and/or the structural unit (a1-2), the total content thereof is the total structure of the resin (A). It is normally 10-95 mol% with respect to the total (100 mol%) of units, Preferably it is 15-90 mol%, More preferably, it is 20-85 mol%.

Further, examples of the structural unit (a1) having the group (1) include the structural unit represented by the formula (a1-3). The structural unit represented by formula (a1-3) is sometimes referred to as "structural unit (a1-3)". The monomer from which the structural unit (a1-3) is derived is sometimes referred to as "monomer (a1-3)".

Here, R ^a9 represents a C ₁ to C ₃ aliphatic hydrocarbon group which may have a hydroxyl group, a carboxy group, a cyano group, -COOR ^a13 or a hydrogen atom.

R ^a13 represents a C ₁ to C ₈ aliphatic hydrocarbon group, a C ₃ to C ₂₀ alicyclic hydrocarbon group, or a group formed by combining them, and a hydrogen atom included in the aliphatic hydrocarbon group and the alicyclic hydrocarbon group is, may be substituted with a hydroxyl group, and the methylene group contained in the aliphatic hydrocarbon group and the alicyclic hydrocarbon group may be substituted with an oxygen atom or a carbonyl group,

R ^a10 , R ^a11 and R ^a12 each independently represent a C ₁ to C ₈ alkyl hydrocarbon group, a C ₃ to C ₂₀ alicyclic hydrocarbon group, or a group formed by combining them, or R ^a10 and R ^a11 are their By bonding with the carbon atom bonded to, it may form a divalent hydrocarbon group of C ₁ to C ₂₀ .

where -COOR ^a13 Examples of the group include a group in which a carbonyl group is bonded to an alkoxy group such as a methoxycarbonyl group and an ethoxycarbonyl group.

Examples of the aliphatic hydrocarbon group which may have a hydroxyl group for R ^a9 include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group and a 2-hydroxyethyl group.

Examples of the C ₁ to C ₈ aliphatic hydrocarbon group of R ^a13 include a methyl group, an ethyl group, a propyl group, an isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group Sil group, n-heptyl group, 2-ethylhexyl group, n-octyl group is included.

Examples of the C ₃ to C ₂₀ alicyclic hydrocarbon group of R ^a13 include a cyclopentyl group, a cyclopropyl group, an adamantyl group, an adamantylmethyl group, a 1-adamantyl-1-methylethyl group, and a 2-oxo-oxo group. a lan-3-yl group and a 2-oxo-oxolan-4-yl group.

Examples of the alkyl group of R ^a10 to R ^a12 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n- a heptyl group, a 2-ethylhexyl group, and an n-octyl group.

Examples of the alicyclic hydrocarbon group of R ^a10 to R ^a12 include a cycloalkyl group, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, monocyclic hydrocarbon groups such as a cyclooctyl group and a cyclodecyl group; and decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1-(adamantan-1-yl)alkan-1-yl group, norbornyl group, methylnorbornyl group and isobornyl group and polycyclic hydrocarbon groups such as the group.

Examples of the group -C(R ^a10 )(R ^a11 )(R ^a12 ) include the following groups when R ^a10 and R ^a11 are bonded together with the carbon atom to which they are bonded to form a divalent hydrocarbon group.

Examples of the monomer (a1-3) are 5-norbornene-2-carboxylic acid-tert-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, 5-norbornene -2-carboxylic acid 1-methylcyclohexyl, 5-norbornene-2-carboxylic acid 2-methyl-2-adamantyl, 5-norbornene-2-carboxylic acid 2-ethyl-2-adamantyl , 5-norbornene-2-carboxylic acid 1-(4-methylcyclohexyl)-1-methylethyl, 5-norbornene-2-carboxylic acid 1-(4-hydroxycyclohexyl)-1-methyl Ethyl, 5-norbornene-2-carboxylic acid 1-methyl-1-(4-oxocyclohexyl)ethyl and 5-norbornene-2-carboxylic acid 1-(1-adamantyl)-1-methyl contains ethyl.

Since the resin (A) having the structural unit (a1-3) has a bulky structure, the resolution of the resulting resist composition can be improved, and a rigid norbornane ring is introduced into the main chain of the resin (A). Therefore, the dry etching resistance of the resist composition obtained can be improved.

When the resin (A) contains the structural unit (a1-3), the content is usually 10 to 95 mol% with respect to the total (100 mol%) of all structural units of the resin (A), preferably is 15 to 90 mol%, more preferably 20 to 85 mol%.

Examples of the structural unit (a1) having the group (2) include the structural unit represented by the formula (a1-4). The structural unit is sometimes referred to as “structural unit (a1-4)”.

Here, R ^a32 represents a hydrogen atom, a halogen atom, or a C ₁ to C ₆ alkyl group which may have a halogen atom.

In each occurrence, R ^a33 is independently a halogen atom, a hydroxy group, a C ₁ to C ₆ alkyl group, a C ₁ to C ₆ alkoxy group, a C ₂ to C ₄ acyl group, a C ₂ to C ₄ acyloxy group , an acryloyloxy group or a methacryloyloxy group.

la represents an integer of 0 to 4.

R ^a34 and R ^a35 each independently represent a hydrogen atom or a C ₁ to C ₁₂ hydrocarbon group, and

R ^a36 represents a C ₁ to C ₂₀ hydrocarbon group, or R ^a35 and R ^a36 may be combined with CO bonded thereto to form a divalent C ₂ to C ₂₀ hydrocarbon group, and the hydrocarbon group and the The methylene group contained in the divalent hydrocarbon group may be substituted with an oxygen atom or a sulfur atom.

Examples of the alkyl group of R ^a32 and R ^a33 include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group and a hexyl group. The alkyl group is preferably a C ₁ to C ₄ alkyl group, more preferably a methyl group or an ethyl group, and more preferably a methyl group.

Examples of the halogen atom of R ^a32 and R ^a33 include a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

Examples of the alkyl group which may have a halogen atom are trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 1,1,1-trifluoroethyl group, 1,1,2,2-tetrafluoro Ethyl group, ethyl group, perfluoropropyl group, 1,1,1,2,2-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2,2,3,3,4,4 -octafluorobutyl group, butyl group, perfluoropentyl group, 1,1,1,2,2,3,3,4,4-nonafluoropentyl group, n-pentyl group, n-hexyl group and n-perfluorohexyl group.

Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group and a hexyloxy group. The alkoxy group is preferably a C ₁ to C ₄ alkoxy group, more preferably a methoxy group or an ethoxy group, and more preferably a methoxy group.

Examples of the acyl group include an acetyl group, a propionyl group and a butyryl group.

Examples of the acyloxy group include an acetyloxy group, a propionyloxy group and a butyryloxy group.

Examples of the hydrocarbon group of R ^a34 and R ^a35 are the same as those described for R ^a1′ to R ^a2′ in formula (2).

Examples of the hydrocarbon group of R ^a36 include a C ₁ to C ₁₈ alkyl group, a C ₃ to C ₁₈ alicyclic hydrocarbon group, a C ₆ to C ₁₈ aromatic hydrocarbon group, or a group formed by combining them.

In formula (a1-4), R ^a32 is preferably a hydrogen atom.

R ^a33 is preferably a C ₁ to C ₄ alkoxy group, more preferably a methoxy group and an ethoxy group, more preferably a methoxy group.

la is preferably 0 or 1, more preferably 0.

R ^a34 is preferably a hydrogen atom.

R ^a35 is preferably a C ₁ to C ₁₂ hydrocarbon group, more preferably a methyl group or an ethyl group.

The hydrocarbon group of R ^a36 is preferably a C ₁ to C ₁₈ alkyl group, a C ₃ to C ₁₈ alicyclic hydrocarbon group, a C ₆ to C ₁₈ aromatic hydrocarbon group, or a group formed by combining them, more preferably a C ₁ to C ₁₈ alkyl group, a C ₃ to C ₁₈ alicyclic aliphatic hydrocarbon group, or a C ₇ to C ₁₈ aralkyl group. The alkyl group and alicyclic hydrocarbon group of R ^a36 are preferably unsubstituted. When the aromatic hydrocarbon group of R ^a36 has a substituent, the substituent is preferably a C ₆ to C ₁₀ aryloxy group.

Examples of the monomer deriving the structural unit (a1-4) include the monomer described in Japanese Patent Application Laid-Open No. 2010-204646. Among these, the monomer is preferably a monomer represented by the following formulas (a1-4-1) to (a1-4-7), more preferably formulas (a1-4-1) to ( a1-4-5).

When the resin (A) contains the structural unit (a1-4), the content is preferably 10-95 mol% with respect to the total (100 mol%) of all structural units of the resin (A), More preferably, it is 15-90 mol%, More preferably, it is 20-85 mol%.

Examples of the structural unit having an acid labile group include a structural unit represented by formula (a1-5). This structural unit is sometimes referred to as "structural unit (a1-5)".

Here, R ^a8 represents a C ₁ to C ₆ alkyl group which may have a halogen atom, a hydrogen atom, or a halogen atom.

Z ^a1 represents a single bond or *-(CH ₂ ) _h3 -CO-L ⁵⁴ -,

h3 represents an integer of 1 to 4,

* represents a bond with L ⁵¹ ,

L ⁵¹ , L ⁵² , and L ⁵³ each independently represent -O- or -S-,

s1 represents an integer of 1 to 3,

s1' represents the integer of 0-3.

In the formula (a1-5), R ^a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group.

L ⁵¹ is preferably -O-,

L ⁵² and L ⁵³ are each independently preferably -O- or -S-, More preferably, one is -O- and the other is -S-.

s1 is preferably 1,

s1' is preferably an integer from 0 to 2.

Z ^a1 is preferably a single bond or *-CH ₂ -CO-O-.

Examples of the monomer deriving the structural unit (a1-5) include the monomer described in Japanese Patent Application Laid-Open No. 2010-61117. Among them, the monomer is preferably a monomer represented by the following formulas (a1-5-1) to (a1-5-4), and more preferably a monomer represented by formulas (a1-5-1) to (a1-). It is a monomer represented by 5-2).

When the resin (A) contains the structural unit (a1-5), the content is usually 1 to 50 mol% with respect to the total (100 mol%) of all structural units of the resin (A), preferably is 3 to 45 mol%, more preferably 5 to 40 mol%.

Examples of the structural unit (a1) having an acid labile group in the resin (A) are preferably the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2) and the structural unit (a1-) 5) at least one kind, more preferably two or more, more preferably a combination of a structural unit (a1-1) and a structural unit (a1-2), and a structural unit (a1-1) from the structural unit selected from the group consisting of 5). ) and a combination of a structural unit (a1-5), a combination of a structural unit (a1-1) and a structural unit (a1-0), a combination of a structural unit (a1-2) and a structural unit (a1-0), a structural unit a combination of (a1-5) and a structural unit (a1-0), a structural unit (a1-0), a combination of a structural unit (a1-1) and a structural unit (a1-2), a structural unit (a1-0); a combination of the structural unit (a1-1) and the structural unit (a1-5), particularly preferably the combination of the structural unit (a1-1) and the structural unit (a1-2) and the structural unit (a1-1) and the structure It is a combination of units (a1-5).

<Structural unit without acid labile group (s)>

The structural unit (s) is derived from a monomer having no acid labile group, which is sometimes referred to as “monomer (s)”.

For the monomer (s) from which the structural unit (s) is derived, a monomer having no known acid-labile group can be used.

As the structural unit (s), a structural unit having a hydroxyl group or a lactone ring and not having an acid labile group is preferable. A structural unit having a hydroxyl group and not having an acid labile group (such a structural unit is sometimes referred to as "structural unit (a2)") and/or a structural unit having a lactone ring and not having an acid labile group (such as When a resin including a structural unit derived from the structural unit (which is sometimes referred to as "structural unit (a3)") is used, the resolution of the resist pattern and the adhesion of the resist with the substrate tend to be improved.

<Structural unit (a2)>

The structural unit (a2) having a hydroxyl group may be an alcoholic hydroxyl group or a phenolic hydroxyl group.

For the resist composition, when a KrF excimer laser (248 nm), or a high energy ray such as an electron beam or EUV (ultra-ultraviolet light) is used, it is preferable to use, as the structural unit (a2), a structural unit having a phenolic hydroxyl group. do.

When an ArF excimer laser (193 nm) is used, it is preferable to use a structural unit having an alcoholic hydroxyl group as the structural unit (a2), and it is more preferable to use a structure represented by the formula (a2-1).

The structural unit (a2) may be used as a single structural unit or as a combination of two or more types of structural units.

The structural unit (a2) having a phenolic hydroxyl group includes a structural unit represented by formula (a2-0) (which is sometimes referred to as “structural unit (a2-0)”).

Here, R ^a30 represents a hydrogen atom, a halogen atom, or a C ₁ to C ₆ alkyl group which may have a halogen atom,

In each case, R ^a31 is a halogen atom, a hydroxy group, a C ₁ to C ₆ alkyl group, a C ₁ to C ₆ alkoxy group, a C ₂ to C ₄ acyl group, a C ₂ to C ₄ acyloxy group, acryl represents a loyloxy group or a methacryloyloxy group,

ma represents an integer of 0 to 4.

Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an n-pentyl group, and an n-hexyl group.

Examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom.

Examples of the C ₁ to C ₆ alkyl group that may have a halogen atom for R ^a30 include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 1,1,1-trifluoroethyl group, 1, 1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 1,1,1,2,2-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2, 2,3,3,4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 1,1,1,2,2,3,3,4,4-nonafluoropentyl group, n -pentyl group, n-hexyl group, and n-perfluorohexyl group.

R ^a30 is preferably a hydrogen atom or a C ₁ to C ₄ alkyl group, more preferably a hydrogen atom, a methyl group or an ethyl group, and more preferably a hydrogen atom or a methyl group.

Examples of the C ₁ to C ₆ alkoxy group of R ^a31 include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group and a hexyloxy group. R ^a31 is preferably a C ₁ to C ₄ alkoxy group, more preferably a methoxy group or an ethoxy group, and more preferably a methoxy group.

Examples of the acyl group include an acetyl group, a propionyl group and a butyryl group.

Examples of the acyloxy group include an acetyloxy group, a propionyloxy group and a butyryloxy group.

ma is preferably 0, 1 or 2, more preferably 0 or 1, more preferably 0.

The structural unit (a2-0) having a phenolic hydroxyl group is preferably a structural unit shown below.

Especially, the structural unit represented by Formula (a2-0-1) or Formula (a2-0-2) is preferable.

Examples of the monomer deriving the structural unit (a2-0) include the monomer described in Japanese Patent Application Laid-Open No. 2010-204634.

The resin (A) comprising the structural unit (a2) having a phenolic hydroxy group is, for example, a monomer in which the phenolic hydroxy group of the monomer deriving the structural unit (a2) having a phenolic hydroxy group is protected with a suitable protecting group. It can be manufactured by carrying out a polymerization reaction using it and carrying out a deprotection process after that. The deprotection treatment is performed in such a way that the acid labile group in the structural unit (a1) is not significantly damaged. Examples of the protecting group for the phenolic hydroxy group include an acetyl group.

When resin (A) contains the structural unit (a2-0) which has a phenolic hydroxyl group, the content rate is 5-95 normally with respect to the total (100 mol%) of all structural units of resin (A). It is mol%, Preferably it is 10-80 mol%, More preferably, it is 15-80 mol%.

Examples of the structural unit (a2) having an alcoholic hydroxyl group include a structural unit represented by formula (a2-1) (which is sometimes referred to as “structural unit (a2-1)”).

Here, L ^a3 represents -O- or *-O-(CH ₂ ) _k2 -CO-O-,

k2 represents an integer of 1 to 7,

* represents a bond with -CO-,

R ^a14 represents a hydrogen atom or a methyl group,

R ^a15 and R ^a16 each independently represent a hydrogen atom, a methyl group or a hydroxy group, and

o1 represents the integer of 0-10.

In the formula (a2-1), L ^a3 is preferably -O-, -O-(CH ₂ ) _f1 -CO-O-, more preferably -O-, wherein f1 is 1 to 4 of represents an integer.

R ^a14 is preferably a methyl group.

R ^a15 is preferably a hydrogen atom.

R ^a16 is preferably a hydrogen atom or a hydroxy group.

o1 becomes like this. Preferably it is an integer of 0-3, More preferably, it is an integer of 0 or 1.

Examples of the monomer deriving the structural unit (a2-1) include the monomer described in Japanese Patent Application Laid-Open No. 2010-204646. Among these, the monomer is preferably a monomer represented by formulas (a2-1-1) to (a2-1-6), more preferably formulas (a2-1-1) to (a2-1-) It is a structural unit represented by 4), More preferably, it is a structural unit represented by a formula (a2-1-1) and a formula (a2-1-3).

Examples of the monomer deriving the structural unit (a2) having an alcoholic hydroxy group include the monomer described in Japanese Patent Application Laid-Open No. 2010-204646.

When the resin (A) contains the structural unit (a2) having an alcoholic hydroxyl group, the content is usually 1 to 45 mol% with respect to the total (100 mol%) of all structural units of the resin (A), Preferably it is 1-40 mol%, More preferably, it is 1-35 mol%, More preferably, it is 2-20 mol%.

< Structural unit (a3) >

The lactone ring included in the structural unit (a3) may be a monocyclic compound such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, and may be a condensed ring of another ring and a monocyclic lactone ring. . Examples of the lactone ring preferably include a γ-butyrolactone ring, an adamantane lactone ring, or a bridging ring including a γ-butyrolactone ring structure.

Examples of the structural unit (a3) include structural units arbitrarily represented by formulas (a3-1), (a3-2), (a3-3) and (a3-4). These structural units may be used as a single unit or may be used as a combination of two or more types of units.

Here, L ^a4 represents *-O- or *-O-(CH ₂ ) _k3 -CO-O-, k3 represents an integer of 1 to 7, * represents a bond with a carbonyl group,

R ^a18 represents a hydrogen atom or a methyl group,

R ^a21 in each case represents a C ₁ to C ₄ aliphatic hydrocarbon group, and

p1 represents an integer from 0 to 5,

L ^a5 represents *-O- or *-O-(CH ₂ ) _k3 -CO-O-, k3 represents an integer of 1 to 7, * represents a bond with a carbonyl group,

R ^a19 represents a hydrogen atom or a methyl group,

R ^a22 in each case represents a carboxy group, a cyano group or a C ₁ to C ₄ aliphatic hydrocarbon group,

q1 represents an integer from 0 to 3,

L ^a6 represents *-O- or *-O-(CH ₂ ) _k3 -CO-O-, k3 represents an integer of 1 to 7, * represents a bond with a carbonyl group,

R ^a20 represents a hydrogen atom or a methyl group,

R ^a23 in each case represents a carboxy group, a cyano group or a C ₁ to C ₄ aliphatic hydrocarbon group, and

r1 represents an integer from 0 to 3,

R ^a24 represents a C ₁ to C ₆ alkyl group which may have a halogen atom, a hydrogen atom or a halogen atom,

L ^a7 is a single bond, *-L ^a8 -O-, *-L ^a8 -CO-O-, *-L ^a8 -CO-OL ^a9 -CO-O- or *-L ^a8 -O-CO-L ^a9 -O-; * represents a bond with a carbonyl group, and

L ^a8 and L ^a9 each independently represent a C ₁ to C ₆ alkanediyl group.

Examples of the aliphatic hydrocarbon group of R ^a21 , R ^a22 and R ^a23 include an alkyl group, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group and a tert-butyl group.

Examples of the halogen atom of R ^a24 include a fluorine atom, a chlorine atom, a bromine atom or an iodine atom,

Examples of the alkyl group of R ^a24 include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group and n-hexyl group, preferably Preferably, a C ₁ to C ₄ alkyl group is mentioned, and more preferably a methyl group or an ethyl group is included.

Examples of the alkyl group having a halogen atom for R ^a24 include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorosec-butyl group, purple Luoro includes a tert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group.

L ^a8 and examples of the alkanediyl group of L ^a9 include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, and a pentane-1,5-diyl group. Diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4 -diyl group and 2-methylbutane-1,4-diyl group.

In formulas (a3-1) to (a3-3), L ^a4 to L ^a6 are each independently of each other, Preferably -O- and k3 are *-O-(CH) represented by an integer of 1 to 4 ₂ ) _k3 -CO-O-, more preferably -O- or *-O-CH ₂ -CO-O-, more preferably *-O-.

R ^a18 to R ^a21 are preferably a methyl group.

R ^a22 and R ^a23 each independently represent a carboxy group, a cyano group or a methyl group.

p1, q1 and r1 each independently represent an integer of preferably 0 to 2, and more preferably 0 or 1.

In the formula (a3-4), R ^a24 is preferably a hydrogen atom or a C ₁ to C ₄ alkyl group, more preferably a hydrogen atom, a methyl group or an ethyl group, and more preferably a hydrogen atom or a methyl group.

L ^a7 is preferably a single bond or *-L ^a8 -CO-O-, and more preferably a single bond, -CH ₂ -CO-O- or -C ₂ H ₄ -CO-O-.

Examples of the monomer deriving the structural unit (a3) include a monomer described in Japanese Patent Application Laid-Open No. 2010-204646, a monomer described in Japanese Patent Application Laid-Open No. 2000-122294, and a monomer described in Japanese Patent Application Laid-Open No. 2012-41274. monomers. Among these, the structural units are preferably the following formulas (a3-1-1) to (a3-1-4), (a3-2-1) to (a3-2-4), and formula (a3) Structural units represented by -3-1) to formulas (a3-3-4) and (a3-4-1) to (a3-4-12), more preferably formula (a3-1-1) ) to the structures represented by the formulas (a3-1-2) and (a3-2-3), (a3-2-4), (a3-4-1) and (a3-4-2) It is a unit, More preferably, it is a structural unit represented by a formula (a3-1-1), a formula (a3-2-3), or a formula (a3-4-2).

When the resin (A) contains the structural unit (a3), the total content is preferably 5 to 70 mol%, more preferably 5 to 70 mol%, based on the total (100 mol%) of all structural units of the resin (A1). Preferably it is 10-65 mol%, More preferably, it is 10-60 mol%.

Each content rate of the structural unit represented by a formula (a3-1), a formula (a3-2), a formula (a3-3), and a formula (a3-4) is the sum total (100 mol) of all the structural units of resin (A) %), preferably 5 to 60 mol%, more preferably 5 to 50 mol%, more preferably 10 to 50 mol%.

< Other structural units (t) >

Resin (A) is a structural unit other than the structural unit (a1) and structural unit (g) described above, comprising other structural units (t) (which are sometimes referred to as "structural units (t)") may be included. Examples of the structural unit (t) are, in addition to the structural unit (a2) and the structural unit (a3), a structural unit having a halogen atom (which is sometimes referred to as "structural unit (a4)"), and a structural unit having a non-delimiting hydrocarbon group (which is sometimes referred to as "structural unit (a5)").

< Structural unit (a4) >

The structural unit having a halogen atom preferably has a fluorine atom.

Examples of the structural unit (a4) include the structural unit represented by formula (a4-0).

Here, R ⁵ represents a hydrogen atom or a methyl group,

L ⁵ represents a single bond or a C ₁ to C ₄ aliphatic saturated hydrocarbon group,

L ³ represents a C ₁ to C ₈ perfluoroalkanediyl group or a C ₅ to C ₁₂ perfluorocycloalkanediyl group, and

R ⁶ represents a hydrogen atom or a fluorine atom.

Examples of the aliphatic saturated hydrocarbon group of L ⁵ include a linear alkanediyl group such as a methylene group, an ethylene group, a propane-1,3-diyl group, and a butane-1,4-diyl group; and a branched alkanediyl group such as a group in which a straight-chain alkanediyl group has a side chain of an alkyl group (eg, a methyl group, an ethyl group), for example, an ethane-1,1-diyl group, a propane-1,2-diyl group , butane-1,3-diyl group, 2-methylpropane-1,3-diyl group and 2-methylpropane-1,2-diyl group.

Examples of the perfluoroalkanediyl group of L ³ are difluoromethylene group, perfluoroethylene group, perfluoroethylfluoromethylene group, perfluoropropane-1,3-diyl group, perfluoropropane- 1,2-diyl group, perfluoropropane-2,2-diyl group, perfluorobutane-1,4-diyl group, perfluorobutane-2,2-diyl group, perfluorobutane-1, 2-diyl group, perfluoropentane-1,5-diyl group, perfluoropentane-2,2-diyl group, perfluoropentane-3,3-diyl group, perfluorohexane-1,6- Diyl group, perfluorohexane-2,2-diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane-1,7-diyl group, perfluoroheptane-2,2-diyl group , perfluoroheptane-3,4-diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1,8-diyl group, perfluorooctane-2,2-diyl group, purple a luorooctane-3,3-diyl group and a perfluorooctane-4,4-diyl group.

Examples of the perfluorocycloalkanediyl group of L ³ include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group and a perfluoroadamantanediyl group.

L ⁵ is preferably a single bond, a methylene group, or an ethylene group, and more preferably a single bond or a methylene group.

L ³ is preferably a C ₁ to C ₆ perfluoroalkanediyl group, and more preferably a C ₁ to C ₃ perfluoroalkanediyl group.

Examples of the structural unit (a4-0) include structural units represented by formulas (a4-0-1) to (a4-0-32).

Examples of the structural unit (a4) include structural units represented by formula (a4-1).

Here, R ^a41 represents a hydrogen atom or a methyl group,

R ^a42 represents an optionally substituted C ₁ to C ₂₀ hydrocarbon group, and the methylene group contained in the hydrocarbon group may be substituted with an oxygen atom or a carbonyl group,

A ^a41 represents an optionally substituted C ₁ to C ₆ alkanediyl group or a group represented by formula (a-g1),

where s represents 0 or 1,

A ^a42 and A ^a44 each independently represent an optionally substituted C ₁ to C ₅ aliphatic hydrocarbon group,

A ^a43 represents a single bond or an optionally substituted C ₁ to C ₅ aliphatic hydrocarbon group, and

X ^a41 and X ^a42 each independently represent -O-, -CO-, -CO-O- or -O-CO-,

provided that the total number of carbon atoms included in the groups of A ^{a42 , A a43 ,} A ^a44 , X ^a41 and X ^a42 is 6 or less, and

At least one of A ^a41 and R ^a42 has a halogen atom as a substituent,

* and ** denote a bond, and * denotes a bond with -O-CO-R ^a42 .

Examples of the hydrocarbon group for R ^a42 include chain and cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups of combinations thereof.

Examples of the chain aliphatic hydrocarbon group are methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-decyl group, n- and alkyl groups, such as dodecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group and n-octadecyl group. Examples of the cyclic alicyclic hydrocarbon group include a monocyclic hydrocarbon group, for example, a cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and decahydronaphthyl group, adamantyl group, norbornyl group, and polycyclic hydrocarbon groups such as the following groups. * indicates a bond.

Examples of the aromatic hydrocarbon group include an aryl group such as a phenyl group, a naphthyl group, an anthryl group, a biphenylyl group, a phenanthryl group and a fluorenyl group.

The hydrocarbon group of R ^a42 is preferably a group of chain and cyclic aliphatic hydrocarbon groups and combinations thereof. The hydrocarbon group may have a carbon-carbon unsaturated bond, and is preferably a chain or cyclic aliphatic saturated hydrocarbon group or a combination thereof.

Examples of the substituent of R ^a42 include a fluorine atom or a group represented by formula (a-g3).

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, preferably a fluorine atom.

Here, X ^a43 represents an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group,

A ^a45 represents a C ₁ to C ₁₇ aliphatic hydrocarbon group having a halogen atom, and

* represents a bond with a carbonyl group.

Examples of the aliphatic hydrocarbon group of A ^a45 are the same as those of the group of R ^a42 .

R ^a42 is preferably an aliphatic hydrocarbon group which may have a halogen atom, more preferably an alkyl group having a halogen atom and/or an aliphatic hydrocarbon group having a group represented by the formula (a-g3).

When R ^a42 is an aliphatic hydrocarbon group having a halogen atom, an aliphatic hydrocarbon group having a fluorine atom is preferable, a perfluoroalkyl group or a perfluorocycloalkyl group is more preferable, and a C ₁ to C ₆ perfluoroalkyl group is more preferable. and a C ₁ to C ₃ perfluoroalkyl group is particularly preferred.

Examples of the perfluoroalkyl group include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, a perfluorohexyl group, a perfluoroheptyl group, and a perfluoro contains a rooctyl group.

Examples of the perfluorocycloalkyl group include a perfluorocyclohexyl group.

When R ^a42 is an aliphatic hydrocarbon group having a group represented by the formula (a-g3), the total number of carbon atoms in the aliphatic hydrocarbon group including the group represented by the formula (a-g3) is preferably 15 or less, more Preferably it is 12 or less. The number of groups represented by the formula (a-g3) is preferably one when the group represented by the formula (a-g3) is a substituent.

The aliphatic hydrocarbon having a group represented by the formula (a-g3) is more preferably a group represented by the formula (a-g2).

Here, A ^a46 represents a C ₁ to C ₁₇ aliphatic hydrocarbon group which may have a halogen atom.

X ^a44 represents a carbonyloxy group or an oxycarbonyl group.

A ^a47 represents a C ₁ to C ₁₇ aliphatic hydrocarbon group which may have a halogen atom,

provided that the total number of carbon atoms included in the groups of A ^a46 , X ^a44 and A ^a47 is 18 or less,

At least one of A ^a46 and A ^a47 has a halogen atom, and

* represents a bond with a carbonyl group.

The number of carbon atoms in the aliphatic hydrocarbon group of A ^a46 is preferably 1 to 6, more preferably 1 to 3.

The aliphatic hydrocarbon group of A ^a47 preferably has 4 to 15 carbon atoms, more preferably 5 to 12 carbon atoms, and more preferably a cyclohexyl group or an adamantyl group as the aliphatic hydrocarbon group.

The preferable structure, *-A ^a46 -X ^a44 -A ^a47 represented by the formula (a-g2) includes the following.

Examples of the alkanediyl group of A ^a41 include a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, and a hexane-1,6-diyl group. a linear alkanediyl group, such as a diary;

Propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group, 2-methylbutane-1,4 - Includes branched alkanediyl groups, such as diyl groups.

Examples of the substituent of the alkanediyl group of A ^a41 include a hydroxyl group and a C ₁ to C ₆ alkoxy group.

delete

A ^a41 is preferably a C ₁ to C ₄ alkanediyl group, more preferably a C ₂ to C ₄ alkanediyl group, and more preferably an ethylene group.

In the group represented by the formula (a-g1) (which is sometimes referred to as "group (a-g1)"), examples of the aliphatic hydrocarbon group of A ^a42 , A ^a43 and A ^a44 are a methylene group, an ethylene group , propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-di diyl, 2-methylpropane-1,2-diyl groups.

Examples of the substituent of the aliphatic hydrocarbon group of A ^a42 , A ^a43 and A ^a44 include a hydroxyl group and a C ₁ to C ₆ alkoxy group.

s is preferably zero.

Examples of the group (a-g1) in which X ^a42 represents an oxygen atom include the following groups. In the formula, * and ** each represent a bond, and ** denotes a bond with -O-CO-R ^a42 .

Examples of the group (a-g1) in which X ^a42 represents a carbonyl group include the following groups.

Examples of the group (a-g1) in which X ^a42 represents a carbonyloxy group include the following groups.

Examples of the group (a-g1) in which X ^a42 is an oxycarbonyl group include the following groups.

The structural unit represented by the formula (a4-1) is preferably a structural unit represented by the formulas (a4-2) and (a4-3).

Here, R ^f1 represents a hydrogen atom or a methyl group,

A ^f1 represents a C ₁ to C ₆ alkanediyl group, and

R ^f2 represents a C ₁ to C ₁₀ hydrocarbon group having a fluorine atom.

Examples of the alkanediyl group of A ^f1 include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, and a pentane-1,5-diyl group. a linear alkanediyl group, such as a diyl group and a hexane-1,6-diyl group;

1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group, 2- branched alkanediyl groups, such as methylbutane-1,4-diyl groups.

The hydrocarbon group of R ^f2 includes an aliphatic hydrocarbon group and an aromatic hydrocarbon group. The aliphatic hydrocarbon group includes groups of chain, cyclic, and combinations thereof. The aliphatic hydrocarbon group is preferably an alkyl group or an alicyclic hydrocarbon group.

Examples of the alkyl group include a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-octyl group and 2- ethylhexyl group.

Examples of the alicyclic hydrocarbon group include any of a monocyclic group and a polycyclic formula. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cycloheptyl group and a cyclo cycloalkyl groups, such as decyl groups. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1-(adamantan-1-yl)alkan-1-yl group, norbor nyl group, methylnorbornyl group and isobornyl group.

Examples of the hydrocarbon group having a fluorine atom for R ^f2 include an alkyl group having a fluorine atom and an alicyclic hydrocarbon group having a fluorine atom.

Specific examples of the alkyl group having a fluorine atom are difluoromethyl group, trifluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, purple Luoroethyl group, 1,1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1- (trifluoromethyl) -1,2,2,2-tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group group, 1,1,2,2,3,3,4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis(trifluoro)methyl-2,2,2-trifluoro Roethyl group, 2-(perfluoropropyl)ethyl group, 1,1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3 ,3,4,4,5,5-decafluoropentyl group, 1,1-bis(trifluoromethyl)-2,2,3,3,3-pentafluoropropyl group, perfluoropentyl group , 2- (perfluorobutyl) ethyl group, 1,1,2,2,3,3,4,4,5,5-decafluorohexyl group, 1,1,2,2,3,3,4 ,4,5,5,6,6-dodecafluorohexyl group, perfluoropentylmethyl group, and perfluorohexyl group, such as a fluorinated alkyl group.

Examples of the alicyclic hydrocarbon group having a fluorine atom include a fluorinated cycloalkyl group, such as a perfluorocyclohexyl group and a perfluoroadamantyl group.

In the formula (a4-2), A ^f1 is preferably a C ₂ to C ₄ alkanediyl group, more preferably an ethylene group.

R ^f2 is preferably a C ₁ to C ₆ fluorinated alkyl group.

Here, R ^f11 represents a hydrogen atom or a methyl group,

A ^f11 represents a C ₁ to C ₆ alkanediyl group,

A ^f13 represents a C ₁ to C ₁₈ aliphatic hydrocarbon group which may have a fluorine atom,

X ^f12 represents a carbonyloxy group or an oxycarbonyl group,

A ^f14 represents a C ₁ to C ₁₇ aliphatic hydrocarbon group which may have a fluorine atom,

However, at least one of A ^f13 and A ^f14 represents an aliphatic hydrocarbon group having a fluorine atom.

Examples of the alkanediyl group of A ^f11 are the same as those of the alkanediyl group of A ^f1 .

Examples of the aliphatic hydrocarbon group of A ^f13 include any of a divalent chain or cyclic hydrocarbon group or a combination thereof. This aliphatic hydrocarbon may have a carbon-carbon unsaturated bond, Preferably it is an aliphatic saturated hydrocarbon group.

The aliphatic hydrocarbon group which may have a fluorine atom as A ^f13 is an aliphatic saturated hydrocarbon group which may have a fluorine atom, and is preferably a perfluoroalkanediyl group.

Examples of the divalent chain aliphatic hydrocarbon group which may have a fluorine atom include an alkanediyl group such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group and a pentanediyl group; perfluoroalkanediyl groups, such as difluoromethylene group, perfluoroethylene group, perfluoropropanediyl group, perfluorobutanediyl group and perfluoropentanediyl group.

The divalent cyclic aliphatic hydrocarbon group which may have a fluorine atom may be any of monocyclic and polycyclic.

Examples of the monocyclic aliphatic hydrocarbon group include a cyclohexanediyl group and a perfluorocyclohexanediyl group.

Examples of the polycyclic aliphatic hydrocarbon group include an adamantanediyl group, a norbornanediyl group, and a perfluoroadamantanediyl group.

Examples of the aliphatic hydrocarbon group of A ^f14 include any one of a chain and cyclic hydrocarbon group, or a combination thereof. This aliphatic hydrocarbon group may have a carbon-carbon unsaturated bond, Preferably it is an aliphatic saturated hydrocarbon group.

The aliphatic hydrocarbon group which may have a fluorine atom as A ^f14 is preferably an aliphatic saturated hydrocarbon group which may have a fluorine atom.

Examples of the chain aliphatic hydrocarbon group which may have a halogen atom are trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 1,1,1-trifluoroethyl group, 1,1,2,2 -tetrafluoroethyl group, ethyl group, perfluoropropyl group, 1,1,1,2,2-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2,2,3,3 ,4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 1,1,1,2,2,3,3,4,4-nonafluoropentyl group, pentyl group, hexyl group, perfluorohexyl group, heptyl group, perfluoroheptyl group, octyl group and perfluorooctyl group.

The cyclic aliphatic hydrocarbon group which may have a halogen atom may be any monocyclic or polycyclic group. Examples of the group containing a monocyclic aliphatic hydrocarbon group include a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, and a perfluorocyclohexyl group. Examples of the group containing the polycyclic aliphatic hydrocarbon group include an adamantyl group, an adamantylmethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group and a perfluoroadamantylmethyl group.

In the formula (a4-3), A ^f11 is preferably an ethylene group.

The aliphatic hydrocarbon group of A ^f13 is preferably a C ₁ to C ₆ aliphatic hydrocarbon group, and more preferably a C ₂ to C ₃ aliphatic hydrocarbon group.

The aliphatic hydrocarbon group of A ^f14 is preferably a C ₃ to C ₁₂ aliphatic hydrocarbon group, and more preferably a C ₃ to C ₁₀ aliphatic hydrocarbon group. Among them, A ^f14 is preferably a group containing a C ₃ to C ₁₂ alicyclic hydrocarbon group, and more preferably a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group and an adamantyl group.

Examples of the structural unit represented by formula (a4-2) include structural units represented by formulas (a4-1-1) to (a4-1-22).

Examples of the structural unit represented by formula (a4-3) include structural units represented by formulas (a4-1'-1) to (a4-1'-22).

Examples of the structural unit (a4) include the structural unit represented by the formula (a4-4).

Here, R ^f21 represents a hydrogen atom or a methyl group,

A ^f21 represents -(CH ₂ ) _j1 -, -(CH ₂ ) _j2 -O-(CH ₂ ) _j3 - or -(CH ₂ ) _j4 -CO-O-(CH ₂ ) _j5 -,

j1 to j5 each independently represent an integer of 1 to 6, and

R ^f22 represents a C ₁ to C ₁₀ hydrocarbon group having a fluorine atom.

Examples of the hydrocarbon group having a fluorine atom of R ^f22 are the same as the examples of the hydrocarbon group described for R ^f2 in the formula (a4-2). R ^f22 is preferably a C ₁ to C ₁₀ alkyl group having a fluorine atom or a C ₃ to C ₁₀ alicyclic hydrocarbon group having a fluorine atom, more preferably a C ₁ to C ₁₀ alkyl group having a fluorine atom and more preferably a C ₁ to C ₆ alkyl group having a fluorine atom.

In the formula (a4-4), A ^f21 is preferably -(CH ₂ ) _j1 -, more preferably an ethylene group or a methylene group, and still more preferably a methylene group.

Examples of the structural unit represented by formula (a4-4) include the following.

When the resin (A) has the structural unit (a4), the content is usually 1 to 20 mol%, preferably 2 to the total (100 mol%) of all structural units of the resin (A). to 15 mol%, more preferably 3 to 10 mol%.

<Structural unit (a5)>

Examples of the non-departing hydrocarbon group of the structural unit (a5) include a straight-chain, branched or cyclic hydrocarbon group. Among these, the structural unit (a5) is preferably a structural unit containing an alicyclic hydrocarbon group.

The structural unit (a5) is, for example, a structural unit represented by formula (a5-1).

Here, R ⁵¹ represents a hydrogen atom or a methyl group,

R ⁵² represents a C ₃ to C ₁₈ alicyclic hydrocarbon group, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a C ₁ to C ₈ aliphatic hydrocarbon group or a hydroxyl group, provided that the carbon bonded to L ⁵¹ A hydrogen atom included in the atom is not substituted with a C ₁ to C ₈ aliphatic hydrocarbon group, and

L ⁵¹ represents a single bond or a C ₁ to C ₁₈ divalent saturated hydrocarbon group, and the methylene group contained in the saturated hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.

Examples of the alicyclic hydrocarbon group for R ⁵² include any of a monocyclic group and a polycyclic group. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic hydrocarbon group include an adamantyl group and a norbornyl group.

Examples of the C ₁ to C ₈ aliphatic hydrocarbon group include a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group , n-heptyl group, 2-ethylhexyl group, and an alkyl group, such as n-octyl group.

Examples of the alicyclic hydrocarbon group having a substituent include a 3-hydroxyadamantyl group and a 3-methyladamantyl group.

R ⁵² is preferably an unsubstituted C ₃ to C ₁₈ alicyclic hydrocarbon group, and more preferably an adamantyl group, a norbornyl group and a cyclohexyl group.

Examples of the divalent saturated hydrocarbon group of L ⁵¹ are a divalent aliphatic saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, and a divalent aliphatic saturated hydrocarbon group is preferable.

Examples of the divalent aliphatic saturated hydrocarbon group include an alkanediyl group, such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group and a pentanediyl group.

The divalent alicyclic saturated hydrocarbon group includes any of a monocyclic group and a polycyclic group. Examples of the monocyclic alicyclic saturated hydrocarbon group include a cycloalkanediyl group, such as a cyclopentanediyl group and a cyclohexanediyl group. Examples of the polycyclic saturated hydrocarbon group include an adamantanediyl group and a norbornanediyl group.

Examples of the group in which the methylene group contained in the saturated hydrocarbon group is substituted with an oxygen atom or a carbonyl group includes groups represented by formulas (L1-1) to (L1-4). In formulas (L1-1) to (L1-4), * represents a bond with an oxygen atom.

Here, X ^x1 represents a carbonyloxy group or an oxycarbonyl group,

L ^x1 represents a C ₁ to C ₁₆ divalent aliphatic saturated hydrocarbon group,

L ^x2 represents a single bond or a divalent saturated hydrocarbon group of C ₁ to C ₁₅ ,

However, the sum total of the total number of carbons contained in the group of L ^x1 and L ^x2 is 16 or less.

L ^x3 represents a single bond or a divalent aliphatic saturated hydrocarbon group of C ₁ to C ₁₇ ,

L ^x4 represents a single bond or a divalent saturated hydrocarbon group of C ₁ to C ₁₆ ,

However, the total of the total number of carbons contained in the group of L ^x3 and L ^x4 is 17 or less.

L ^x5 represents a C ₁ to C ₁₅ divalent aliphatic saturated hydrocarbon group,

L ^x6 and L ^x7 are each independently a single bond or a C ₁ to C ₁₄ divalent aliphatic saturated hydrocarbon group,

However, the total of the total number of carbons contained in the group of L ^x5 , L ^x6 and L ^x7 is 15 or less.

L ^x8 and L ^x9 are each independently a single bond or a C ₁ to C ₁₂ divalent saturated hydrocarbon group,

W ^x1 represents a divalent alicyclic saturated hydrocarbon group of C ₃ to C ₁₅ ,

However, the total of the total number of carbons contained in the group of L ^x8 , L ^x9 and W ^x1 is 15 or less.

L ^x1 is preferably a C ₁ to C ₈ divalent aliphatic saturated hydrocarbon group, more preferably a methylene group or an ethylene group.

L ^x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group of C ₁ to C ₈ , more preferably a single bond.

L ^x3 is preferably a C ₁ to C ₈ divalent aliphatic saturated hydrocarbon group.

L ^x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group of C ₁ to C ₈ .

L ^x5 is preferably a C ₁ to C ₈ divalent aliphatic saturated hydrocarbon group, more preferably a methylene group or an ethylene group.

L ^x6 is preferably a single bond or a C ₁ to C ₈ divalent aliphatic saturated hydrocarbon group, more preferably a methylene group or an ethylene group.

L ^x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group of C ₁ to C ₈ .

L ^x8 is preferably a single bond or a C ₁ to C ₈ divalent aliphatic saturated hydrocarbon group, more preferably a single bond or a methylene group.

L ^x9 is preferably a single bond or a C ₁ to C ₈ divalent aliphatic saturated hydrocarbon group, more preferably a single bond or a methylene group.

W ^x1 is preferably a C ₃ to C ₁₀ divalent alicyclic saturated hydrocarbon group, more preferably a cyclohexanediyl group or an adamantanediyl group.

Examples of the group represented by formula (L1-1) include the following.

Examples of the group represented by the formula (L1-2) include the following.

Examples of the group represented by formula (L1-3) include the following.

Examples of the group represented by formula (L1-4) include the following.

L ⁵¹ is preferably a single bond, a methylene group, an ethylene group, or a group represented by the formula (L1-1), and more preferably a single bond or a group represented by the formula (L1-1).

Examples of the structural unit (a5-1) include the following.

When the resin (A) has the structural unit (a5), the content is usually 1 to 30 mol%, preferably 2 to the total (100 mol%) of all structural units of the resin (A). to 20 mol%, more preferably 3 to 15 mol%.

The resin (A) may further contain structural units other than the structural units described above. Examples of the structural unit include known structural units.

The resin (A) is preferably a resin having a structural unit (a1) and a structural unit (s), that is, a copolymer of a monomer (a1) and a monomer (s). In the copolymer, the structural unit (a1) preferably has a structural unit (a1-0), a structural unit (a1-1), and a structural unit (a1-2) (preferably having a cyclohexyl group or a cyclopentyl group) at least one of the structural unit) and the structural unit (a1-5), more preferably the structural unit (a1-1) and the structural unit (a1-2) (preferably having a cyclohexyl group or a cyclopentyl group) structural unit).

The structural unit (s) is preferably at least one of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably a structural unit represented by formula (a2-1). The structural unit (a3) is preferably a structural unit (a3-1-1) to (a3-1-4), a structural unit (a3-2-1) to (a3-2-4), a structural unit (a3) It is at least 1 sort(s) of the structural unit containing 3--1)-(a3-3-4) and structural unit (a3-4-1)-(a3-4-2).

In the resin (A), the content of the structural unit derived from the monomer having an adamantyl group (in particular, the structural unit (a1-1)) is preferably 15 mol% or more with respect to the structural unit (a1). As the molar ratio of the structural unit derived from the monomer having an adamantyl group increases within this region, the dry etching resistance of the obtained resist improves.

Resin (A) can be manufactured by a well-known polymerization method, for example, a radical polymerization method using at least 1 said structural unit. The content rate of the structural unit in resin (A) can be adjusted by the usage-amount of the monomer used for superposition|polymerization.

The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, more preferably 3,000 or more), and 50,000 or less (more preferably 30,000 or less, more preferably 15,000 or less).

The weight average molecular weight is a value measured by gel permeation chromatography using polystyrene as a standard product. The detailed conditions of this assay are described in the Examples.

When the resist composition contains the resin (X), the content is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, more preferably 1 to 50 parts by mass, based on the resin (A) (100 parts by mass). Preferably it is 1-40 mass parts, Especially preferably, it is 2-30 mass parts.

The total content of the resin (A) and the resin (X) is preferably 80 mass% to 99 mass%, more preferably 90 mass% to 99 mass%, based on the solid content of the resist composition. The solid content content of the resist composition can be measured by a known analysis method such as liquid chromatography or gas chromatography, for example.

< Resins other than Resin (A) and Resin (X) >

The resist composition of the present invention may contain a resin other than the resin (A) and the resin (X). The resin may be a resin having no structural unit (a1). Examples of such a resin include a resin containing only the structural unit (s).

The resin is preferably a resin comprising the structural unit (a4) (which is sometimes referred to as “resin (Y)”). In the resin (Y), the content of the structural unit (a4) is preferably 40 mol% or more, more preferably 45 mol% or more with respect to the total (100 mol%) of all structural units constituting the resin (Y). It is mol% or more, More preferably, it is 50 mol% or more.

Examples of the structural unit that the resin (Y) may further include include the structural unit (a2), the structural unit (a3), and other structural units derived from known monomers.

The weight average molecular weight of the resin (Y) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less). The method of measuring the weight average molecular weight of resin (Y) is the same as that in the case of resin (A).

When the resist composition contains the resin (Y), the content thereof is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, still more preferably 1 to 60 parts by mass relative to the resin (100 parts by mass). It is 1-40 mass parts, Especially preferably, it is 2-30 mass parts.

The total content of the resin (X), the resin (A) and the resin (Y) is preferably 80 mass% to 99 mass%, more preferably 90 mass% to 99 mass%, based on the solid content of the resist composition. .

<Acid generator (B)>

The acid generator (B) may be an ionic acid generator or a nonionic generator. The acid generator (B) can be used as any ionic acid generator and a nonionic generator. Examples of the nonionic compound for the acid generator include organic halides; sulfonate esters such as 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4-sulfonate; sulfones such as disulfone, ketosulfone, and sulfonyldiazomethane. The ionic compound for the acid generator includes an onium salt having an onium cation, for example, a diazonium salt, a phosphonium salt, a sulfonium salt and an iodonium salt. Examples of the anion of the onium salt include a sulfonic acid anion, a sulfonylimide anion, and a sulfonylmethide anion.

As an acid generator (B), Unexamined-Japanese-Patent No. 63-26653, Unexamined-Japanese-Patent No. 55-164824, Unexamined-Japanese-Patent No. 62-69263, Unexamined-Japanese-Patent No. 63-146038, Unexamined-Japanese-Patent No. Japanese Patent Laid-Open No. 63-163452, Japanese Patent Application Laid-Open No. 62-153853, Japanese Patent Laid-Open No. 63-146029, U.S. Patent No. 3,779,778, U.S. Patent No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712 It is possible to use compounds which generate acids by radiation as described in the heading. Moreover, you may use the compound manufactured by a well-known method.

The acid generator (B) is preferably a fluorine-containing acid generator, more preferably a salt represented by the formula (B1) (which is sometimes referred to as “acid generator (B1)”).

Here, Q ¹ and Q ² each independently represent a fluorine atom or a C ₁ to C ₆ perfluoroalkyl group,

L ^b1 represents a C ₁ to C ₂₄ divalent saturated hydrocarbon group, the methylene group contained in the saturated hydrocarbon group may be substituted with an oxygen atom or a carbonyl group, and a hydrogen atom contained in the saturated hydrocarbon group is substituted with a hydroxyl group or a fluorine atom may be,

Y represents an optionally substituted C ₃ to C ₁₈ alicyclic hydrocarbon group, and the methylene group contained in the alicyclic hydrocarbon group may be substituted with an oxygen atom, a carbonyl group or a sulfonyl group,

Z ⁺ represents an organic cation.

Examples of the perfluoroalkyl group of Q ¹ and Q ² include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, and a perfluorosec-butyl group. , a perfluoro tert-butyl group, a perfluoropentyl group and a perfluorohexyl group.

Each of Q ¹ and Q ² is preferably a trifluoromethyl group or a fluorine atom, more preferably Q ¹ and Q ² are both a fluorine atom.

Examples of the divalent saturated hydrocarbon group of L ^b1 include a linear or branched alkanediyl group, a divalent monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group combining these groups.

Specific examples of the linear alkanediyl group include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, and a pentane-1,5-diyl group. Diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane -1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane -1,16-diyl group and heptadecane-1,17-diyl group.

Specific examples of the branched alkanediyl group include ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-1, 4-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 2-methylbutane-1,4-diyl group include

Specific examples of the monocyclic alicyclic saturated hydrocarbon group include a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, and a cyclooctane-1,5-diyl group. cycloalkanediyl groups, such as diyl groups.

Specific examples of the polycyclic alicyclic saturated hydrocarbon group include norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane- 2,6-diyl groups.

Examples of the saturated hydrocarbon group of L ^b1 in which the methylene group is substituted with an oxygen atom or a carbonyl group include groups represented by formulas (b1-1) to (b1-3).

Here, L ^b2 represents a single bond or a C ₁ to C ₂₂ divalent saturated hydrocarbon group, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom,

L ^b3 represents a single bond or a C ₁ to C ₂₂ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group, and a methylene group contained in the saturated hydrocarbon group is an oxygen atom Or may be substituted with a carbonyl group,

However, the total number of carbon atoms included in the groups of L ^b2 and L ^b3 is 22 or less,

L ^b4 represents a single bond or a C ₁ to C ₂₂ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom,

L ^b5 represents a single bond or a C ₁ to C ₂₂ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group, and a methylene group contained in the saturated hydrocarbon group is an oxygen atom Or may be substituted with a carbonyl group,

However, the total number of carbon atoms included in the groups of L ^b4 and L ^b5 is 22 or less,

L ^b6 represents a single bond or a C ₁ to C ₂₃ divalent saturated hydrocarbon group, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group;

L ^b7 represents a single bond or a C ₁ to C ₂₃ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group, and a methylene group contained in the saturated hydrocarbon group is an oxygen atom Or may be substituted with a carbonyl group,

However, the total number of carbon atoms contained in the groups of L ^b6 and L ^b7 is 23 or less,

* represents a bond with -Y.

In formulas (b1-1) to (b1-3), when the saturated methylene group is substituted with an oxygen atom or a carbonyl group, the number of carbon atoms in the saturated hydrocarbon group corresponds to the number of carbon atoms before substitution.

For formulas (b1-1) to (b1-3), examples of the divalent saturated hydrocarbon group include an alkanediyl group and a monocyclic or polycyclic divalent saturated hydrocarbon group, and combinations of two or more of these groups include that

Examples of the divalent saturated hydrocarbon group are the same as those of the divalent saturated hydrocarbon group of L ^b1 .

L ^b2 is preferably a single bond.

L ^b3 is preferably a C ₁ to C ₄ divalent saturated hydrocarbon group.

L ^b4 is preferably a C ₁ to C ₈ divalent saturated hydrocarbon group, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom.

L ^b5 is preferably a single bond or a divalent saturated hydrocarbon group of C ₁ to C ₈ .

L ^b6 is preferably a single bond or a divalent saturated hydrocarbon group of C ₁ to C ₄ , and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom.

L ^b7 is preferably a single bond or a C ₁ to C ₁₈ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group, and methylene contained in the saturated hydrocarbon group The group may be substituted with an oxygen atom or a carbonyl group.

Especially, the group represented by a formula (b1-1) or a formula (b1-3) is preferable.

Examples of the divalent group represented by the formula (b1-1) include groups represented by the following formulas (b1-4) to (b1-8).

Here, L ^b8 represents a single bond or a C ₁ to C ₂₂ divalent saturated hydrocarbon group, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group,

L ^b9 represents a C ₁ to C ₂₀ divalent saturated hydrocarbon group,

L ^b10 represents a single bond or a C ₁ to C ₁₉ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group;

However, the total number of carbon atoms included in the groups of L ^b9 and L ^b10 is 20 or less,

L ^b11 represents a C ₁ to C ₂₁ divalent saturated hydrocarbon group,

L ^b12 represents a single bond or a C ₁ to C ₂₀ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group;

However, the total number of carbon atoms included in the groups of L ^b11 and L ^b12 is 21 or less,

L ^b13 represents a divalent saturated hydrocarbon group of C ₁ to C ₁₉ ,

L ^b14 represents a single bond or a divalent saturated hydrocarbon group of C ₁ to C ₁₈ ,

L ^b15 represents a single bond or a C ₁ to C ₁₈ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group;

provided that the total number of carbon atoms contained in the groups of L ^b13 , L ^b14 and L ^b15 is 19 or less,

L ^b16 represents a C ₁ to C ₁₈ divalent saturated hydrocarbon group,

L ^b17 represents a C ₁ to C ₁₈ divalent saturated hydrocarbon group.

L ^b18 represents a single bond or a C ₁ to C ₁₇ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxyl group;

However, the total number of carbon atoms contained in the groups of L ^b16 , L ^b17 and L ^b18 is 19 or less.

L ^b8 is preferably a C ₁ to C ₄ divalent saturated hydrocarbon group.

L ^b9 is preferably a C ₁ to C ₈ divalent saturated hydrocarbon group.

L ^b10 is preferably a single bond or a C ₁ to C ₁₉ divalent saturated hydrocarbon group, and more preferably a single bond or a C ₁ to C ₈ divalent saturated hydrocarbon group.

L ^b11 is preferably a C ₁ to C ₈ divalent saturated hydrocarbon group.

L ^b12 is preferably a single bond or a divalent saturated hydrocarbon group of C ₁ to C ₈ .

L ^b13 is preferably a C ₁ to C ₁₂ divalent saturated hydrocarbon group.

L ^b14 is preferably a single bond or a divalent saturated hydrocarbon group of C ₁ to C ₆ .

L ^b15 is preferably a single bond or a C ₁ to C ₁₈ divalent saturated hydrocarbon group, and more preferably a single bond or a C ₁ to C ₈ divalent saturated hydrocarbon group.

L ^b16 preferably represents a C ₁ to C ₁₂ divalent saturated hydrocarbon group.

L ^b17 preferably represents a C ₁ to C ₆ divalent saturated hydrocarbon group.

L ^b18 is preferably a single bond or a C ₁ to C ₁₇ divalent saturated hydrocarbon group, and more preferably a single bond or a C ₁ to C ₄ divalent saturated hydrocarbon group.

Examples of the divalent group represented by the formula (b1-3) include groups represented by the following formulas (b1-9) to (b1-11).

Here, L ^b19 represents a single bond or a C ₁ to C ₂₃ divalent saturated hydrocarbon group, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom.

L ^b20 represents a single bond or a C ₁ to C ₂₃ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxyl group or an acyloxy group, and the methylene group contained in the acyloxy group is , an oxygen atom or a carbonyl group may be substituted, and the hydrogen atom contained in the acyloxy group may be substituted with a hydroxyl group,

provided that the total number of carbon atoms in the groups of L ^b19 and L ^b20 is 23 or less,

L ^b21 represents a single bond or a C ₁ to C ₂₁ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom;

L ^b22 represents a single bond or a C ₁ to C ₂₁ divalent saturated hydrocarbon group,

L ^b23 represents a single bond or a C ₁ to C ₂₁ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxyl group or an acyloxy group, and the methylene group contained in the acyloxy group is , an oxygen atom or a carbonyl group may be substituted, and the hydrogen atom contained in the acyloxy group may be substituted with a hydroxyl group,

provided that the total number of carbon atoms included in the groups of L ^b21 , L ^b22 and L ^b23 is 21 or less,

L ^b24 represents a single bond or a C ₁ to C ₂₀ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom,

L ^b25 represents a single bond or a C ₁ to C ₂₁ divalent saturated hydrocarbon group,

L ^b26 represents a single bond or a C ₁ to C ₂₀ divalent saturated hydrocarbon group, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxyl group or an acyloxy group, and the methylene group contained in the acyloxy group is , an oxygen atom or a carbonyl group may be substituted, and the hydrogen atom contained in the acyloxy group may be substituted with a hydroxyl group,

However, the total number of carbon atoms contained in the groups of L ^b24 , L ^b25 and L ^b26 is 21 or less.

In formulas (b1-9) to (b1-11), when a hydrogen atom included in the saturated hydrocarbon group is substituted with an acyloxy group, the number of carbon atoms in the saturated hydrocarbon group is added to the carbon number of the saturated hydrocarbon group, and carbon atoms, CO and O corresponds to the number of

For formulas (b1-9) to (b1-11), examples of the divalent saturated hydrocarbon group include an alkanediyl group and a monocyclic or polycyclic divalent saturated hydrocarbon group, and combinations of two or more of these groups include that

Examples of the acyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, a cyclohexylcarbonyloxy group, and an adamantylcarbonyloxy group.

Examples of the acyloxy group having a substituent include an oxoadamantylcarbonyloxy group, a hydroxyadamantylcarbonyloxy group, an oxocyclohexylcarbonyloxy group, and a hydroxycyclohexylcarbonyloxy group.

Examples of the group represented by formula (b1-4) include the following.

Examples of the group represented by formula (b1-5) include the following.

Examples of the group represented by the formula (b1-6) include the following.

Examples of the group represented by the formula (b1-7) include the following.

Examples of the group represented by formula (b1-8) include the following.

Examples of the group represented by the formula (b1-2) include the following.

Examples of the group represented by the formula (b1-9) include the following.

Examples of the group represented by formula (b1-10) include the following.

Examples of the group represented by the formula (b1-11) include the following.

Examples of the monovalent alicyclic hydrocarbon group of Y include groups represented by formulas (Y1) to (Y11).

Examples of the monovalent alicyclic hydrocarbon group of Y in which a methylene group is substituted with an oxygen atom, a carbonyl group or a sulfonyl group include groups represented by formulas (Y12) to (Y27).

Among them, the alicyclic hydrocarbon group is preferably an arbitrary group among the groups represented by formulas (Y1) to (Y19), more preferably formula (Y11), formula (Y14), formula (Y15) or formula ( It is an arbitrary group among the groups represented by Y19), More preferably, it is group represented by a formula (Y11) or a formula (Y14).

Examples of the substituent of the alicyclic group represented by Y include a halogen atom, a hydroxyl group, a C ₁ to C ₁₂ alkyl group, a C ₁ to C ₁₂ hydroxyl group-containing alkyl group, a C ₃ to C ₁₆ monovalent alicyclic hydrocarbon group, C ₁ To C ₁₂ Alkoxy group, C ₆ To C ₁₈ Monovalent aromatic hydrocarbon group, C ₇ To C ₂₁ Aralkyl group, C ₂ To C ₄ Acyl group, glycidyloxy group, and -(CH) _ja -O-CO-R ^b1 group, wherein R ^b1 represents a C ₁ to C ₁₆ alkyl group, a C ₃ to C ₁₆ monovalent alicyclic hydrocarbon group, or a C ₆ to C ₁₈ monovalent aromatic hydrocarbon group , ja represents an integer of 0 to 4.

Examples of the hydroxy group-containing alkyl group include a hydroxymethyl group and a hydroxyethyl group.

Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group and a dodecyloxy group.

Examples of the monovalent aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, and an aryl group such as a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group.

Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group and a naphthylethyl group.

Examples of the acyl group include an acetyl group, a propionyl group and a butyryl group.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of Y include the following groups. * is a bond with L ^b1 .

Y is preferably a C ₃ to C ₁₈ monovalent alicyclic hydrocarbon group which may have a substituent, more preferably an adamantyl group which may have a substituent, and at least one methylene group contained in the adamantyl group, It may be substituted with an oxygen atom, a sulfonyl group, or a carbonyl group, More preferably, they are an adamantyl group, a hydroxyadamantyl group, or an oxoadamantyl group.

The sulfonic acid anion in the salt represented by formula (B1) is preferably an anion represented by the following formulas (B1-A-1) to (B1-A-33), more preferably a formula (B1-A-1) to formula (B1-A-4), formula (B1-A-9), formula (B1-A-10), formula (B1-A-24) to formula (B1-A- 33) is an anion.

Further, in formulas (B1-A-1) to (B1-A-33), R ⁱ² to R ⁱ⁷ are each independently, for example, a C ₁ to C ₄ alkyl group, preferably a methyl group or an ethyl group. and R ⁱ⁸ is, for example, a C ₁ to C ₁₂ aliphatic hydrocarbon group, preferably a C ₁ to C ₄ alkyl group, a C ₅ to C ₁₂ monovalent alicyclic hydrocarbon group, or a group formed by combining them; More preferably, a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group is shown. L ⁴ represents a single bond or a C ₁ to C ₄ alkanediyl group. Q ¹ and Q ² have the same meaning as defined above.

Specific examples of the sulfonic acid anion in the salt represented by the formula (B1) include the anion described in JP 2010-204646 A .

Among them, preferred examples of the sulfonic acid anion for the salt represented by the formula (B1) include the anions represented by the formulas (B1a-1) to (B1a-15).

Among them, preferred examples of the sulfonic acid anion include anions represented by the formulas (B1a-1) to (B1a-3) and (B1a-7) to (b1a-15).

Organic cations represented by Z ⁺ include organic onium cations, such as organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, organic phosphonium cations, A sulfonium cation or an organic iodonium cation is preferable, and an arylsulfonium cation is more preferable.

Z ⁺ in formula (B1) is preferably represented by any of formulas (b2-1) to (b2-4).

Here, R ^b4 , R ^b5 and R ^b6 each independently represent a C ₁ to C ₃₀ aliphatic hydrocarbon group, a C ₃ to C ₃₆ alicyclic hydrocarbon group or a C ₆ to C ₃₆ aromatic hydrocarbon group, and the aliphatic hydrocarbon The hydrogen atom included in the group may be substituted with a hydroxyl group, a C ₁ to C ₁₂ alkoxy group, a C ₃ to C ₁₂ alicyclic hydrocarbon group or a C ₆ to C ₁₈ aromatic hydrocarbon group, and is included in the alicyclic hydrocarbon group The hydrogen atom may be substituted with a halogen atom, a C ₁ to C ₁₈ aliphatic hydrocarbon group, a C ₂ to C ₄ acyl group or a glycidyloxy group, and the hydrogen atom contained in the aromatic hydrocarbon group is a halogen atom or a hydroxyl group. Alternatively, it may be substituted with a C ₁ to C ₁₂ alkoxy group, or R ^b4 and R ^b5 may be bonded together with a sulfur atom to which they are bonded to form a ring containing sulfur, and the methylene group contained in the ring is oxygen may be substituted with an atom, a sulfur atom or a carbonyl group,

R ^b7 and R ^b8 in each occurrence, each independently represent a hydroxyl group, a C ₁ to C ₁₂ aliphatic hydrocarbon group or a C ₁ to C ₁₂ alkoxy group,

m2 and n2 each independently represent the integer of 0-5.

R ^b9 and R ^b10 each independently represent a C ₁ to C ₃₆ aliphatic hydrocarbon group or a C ₃ to C ₃₆ alicyclic hydrocarbon group, or R ^b9 and R ^b10 are bonded together with a sulfur atom bonded thereto A ring containing sulfur may be formed, and the methylene group contained in the ring may be substituted with an oxygen atom, a sulfur atom, or a carbonyl group,

R ^b11 represents a hydrogen atom, a C ₁ to C ₃₆ aliphatic hydrocarbon group, a C ₃ to C ₃₆ alicyclic hydrocarbon group, or a C ₆ to C ₁₈ aromatic hydrocarbon group,

R ^b12 represents a C ₁ to C ₁₂ aliphatic hydrocarbon group, a C ₃ to C ₁₈ alicyclic hydrocarbon group or a C ₆ to C ₁₈ aromatic hydrocarbon group, and a hydrogen atom included in the aliphatic hydrocarbon is C ₆ to C ₁₈ may be substituted with an aromatic hydrocarbon group, and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a C ₁ to C ₁₂ alkoxy group or a C ₁ to C ₁₂ alkylcarbonyloxy group,

R ^b11 and R ^b12 may be bonded together with -CH-CO- to which they are bonded to form a ring, and the methylene group contained in the ring may be substituted with an oxygen atom, a sulfur atom or a carbonyl group,

R ^b13 , R ^b14 , R ^b15 , R ^b16 , R ^b17 , and R ^b18 in each case independently represent a hydroxy group, a C ₁ to C ₁₂ aliphatic hydrocarbon group or a C ₁ to C ₁₂ alkoxy group,

L ^b31 represents -S- or -O-,

o2, p2, s2, and t2 each independently represent an integer of 0 to 5;

q2 and r2 each independently represent an integer of 0 to 4, and

u2 represents an integer of 0 or 1.

Examples of the aliphatic hydrocarbon group are preferably methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n- octyl group and 2-ethylhexyl group. Among them, R ^b9 The aliphatic hydrocarbon group of to R ^b12 is preferably a C ₁ to C ₁₂ aliphatic hydrocarbon group.

Examples of the alicyclic hydrocarbon group are preferably monocyclic, such as a cycloalkyl group, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group. flags; and decahydronaphthyl group, adamantyl group, norbornyl group, and polycyclic hydrocarbon groups such as the following groups.

Among them, R ^b9 The alicyclic hydrocarbon group of to R ^b12 is preferably a C ₃ to C ₁₈ alicyclic group, and more preferably a C ₄ to C ₁₂ alicyclic hydrocarbon group.

Examples of the alicyclic hydrocarbon group in which a hydrogen atom may be substituted with an aliphatic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-alkyladamantan-2-yl group, a methylnorbornyl group, and an isobornyl group. In the alicyclic hydrocarbon group in which a hydrogen atom may be substituted with an aliphatic hydrocarbon group, the total number of carbon atoms in the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less.

Examples of the aromatic hydrocarbon group are preferably a phenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a p-cyclohexylphenyl group, a p-adamantylphenyl group, and an aryl group such as a biphenylyl group, a naphthyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group.

When the aromatic hydrocarbon group includes an aliphatic hydrocarbon group or an alicyclic hydrocarbon group, a C ₁ to C ₁₈ aliphatic hydrocarbon group or a C ₃ to C ₁₈ alicyclic hydrocarbon group is preferable.

Examples of the aromatic hydrocarbon group in which a hydrogen atom may be substituted with an alkoxy group include a p-methoxyphenyl group.

Examples of the aliphatic hydrocarbon group in which a hydrogen atom may be substituted with an aromatic hydrocarbon group include an aralkyl group, such as a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group.

Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, and a dodecyloxy group.

Examples of the acyl group include an acetyl group, a propionyl group and a butyryl group.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of the alkylcarbonyloxy group are methylcarbonyloxy group, ethylcarbonyloxy group, n-propylcarbonyloxy group, isopropylcarbonyloxy group, n-butylcarbonyloxy group, sec-butylcarbonyloxy group group, tert-butylcarbonyloxy group, pentylcarbonyloxy group, hexylcarbonyloxy group, octylcarbonyloxy group and 2-ethylhexylcarbonyloxy group.

The ring including the sulfur atom formed by R ^b4 and R ^b5 may be a monocyclic or polycyclic ring, an aromatic or non-aromatic ring, and may be a saturated or unsaturated ring. This ring is preferably a ring having 3 to 8 carbon atoms, more preferably a ring having 4 to 13 carbon atoms. Examples of the ring containing a sulfur atom include a 3- to 12-membered ring, preferably a 3- to 7-membered ring, and examples thereof include the following ring.

Examples of the ring formed by R ^b9 and R ^b10 may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring. Examples of the ring include a thiolan-1-ium ring (tetrahydrothiophenium ring), a thiane-1-ium ring, and a 1,4-oxathian-4-ium ring.

R ^b11 And examples of the ring formed by R ^b12 may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring. Examples of the ring include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

Among the cations represented by the formulas (b2-1) to (b2-4), the cation represented by the formula (b2-1) is preferable, and the cation represented by the formula (b2-1-1) is More preferably, triphenylsulfonium cation (in formula (b2-1-1), v2=w2=x2=0), diphenyltolylsulfonium cation (in formula (b2-1-1), v2= w2=0, x2=1, and R ^b21 is a methyl group) or tritolylsulfonium cation (in formula (b2-1-1), v2=w2=x2=1, and R ^b19 , R ^b20 and R ^b21 are all methyl groups.) is more preferable.

Here, R ^b19 , R ^b20 and R ^b21 are, in each case, each independently a halogen atom, a hydroxyl group, a C ₁ to C ₁₈ aliphatic hydrocarbon group, or a C ₃ to C ₁₈ alicyclic hydrocarbon group Alternatively, it may represent a C ₁ to C ₁₂ alkoxy group, or two from R ^b19 , R ^b20 and R ^b21 may combine to form a ring containing a sulfur atom.

In the formula (b1-1-1), the ring including two sulfur atoms formed by R ^b19 , R ^b20 and R ^b21 may be a monocyclic or polycyclic ring. The ring may be aromatic or non-aromatic. The ring may be a saturated or unsaturated ring. The ring may further have additional sulfur atoms and/or oxygen atoms.

The alkyl group of R ^b19 , R ^b20 and R ^b21 is preferably a C ₁ to C ₁₂ aliphatic hydrocarbon group. The alicyclic hydrocarbon group of R ^b19 , R ^b20 and R ^b21 is preferably a C ₄ to C ₁₈ alicyclic hydrocarbon group.

R ^b19 , R ^b20 and R ^b21 each independently preferably represent a halogen atom (more preferably a fluorine atom), a hydroxy group, a C ₁ to C ₁₂ aliphatic hydrocarbon group or a C ₁ to C ₁₂ alkoxy group, or two from R ^b19 , R ^b20 and R ^b21 are preferably joined to form a ring comprising a sulfur atom, and

v2, w2 and x2 each independently preferably represent 0 or 1.

Specific examples of organic cations represented by formulas (b2-1) to (b2-4) and (b2-1-1) are, for example, compounds described in Japanese Patent Application Laid-Open No. 2010-204646. include

An acid generator (B1) is a compound normally comprised from an organic cation and said sulfonic acid anion. The sulfonic acid anion and the organic cation may be selectively combined. A preferred combination is any of the anions represented by the formulas (B1a-1) to (B1a-3) and (B1a-7) to (B1a-15) with the formula (b2-1-1) or the formula It is a combination with the cation represented by (b2-3).

Preferred acid generators (B1) are preferably represented by formulas (B1-1) to (B1-30). Among them, formula (B1-1), formula (B1-2), formula (B1-3), formula (B1-5), formula (B1-6), formula (B1-) containing an arylsulfonium cation 7), formula (B1-11), formula (B1-12), formula (B1-13), formula (B1-14), formula (B1-17), formula (B1-20), formula (B1-21) ), a formula (B1-23), a formula (B1-24), a formula (B1-25), a formula (B1-26) or a formula (B1-29) are preferable.

The content of the acid generator (B1) is preferably 30% by mass or more and 100% by mass or less, and more preferably 50% by mass or more and 100% by mass or less with respect to 100% by mass of the total amount of the acid generator (B). and more preferably substantially 100% by mass.

In the resist composition of the present invention, the content of the acid generator (B) is preferably 1 part by mass or more, more preferably 3 parts by mass or more, with respect to 100 parts by mass of the resin (A), preferably It is 30 mass parts or less, More preferably, it is 25 mass parts or less.

In the resist composition of the present invention, the acid generator (B) can be used as a single salt or a combination of two or more salts.

< Solvent (E) >

The content rate of the solvent (E) is normally 90 mass % or more, Preferably it is 92 mass % or more, More preferably, it is 94 mass % or more, More preferably, it is 99 mass % or less, More preferably, it is 99.9 mass % or more. mass% or less. The content of the solvent (E) can be measured by a known analytical method such as liquid chromatography or gas chromatography.

Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; and cyclic esters such as γ-butyrolactone. These solvents (E) can be used as a single solvent or as a mixture of two or more solvents.

< Where to go (C) >

The resist composition of the present invention may contain a substance such as a basic nitrogen-containing organic compound or a salt that generates an acid having a weaker acidity than the acid generated from the acid generator.

The content rate of the oxidizing agent is preferably 0.01 to 5 mass % with respect to the total amount of solid content of the resist composition.

Examples of the basic nitrogen-containing organic compound include amines and ammonium salts. The amine may be an aliphatic amine or an aromatic amine. The aliphatic amine includes any one of a primary amine, a secondary amine, and a tertiary amine.

Specific examples of amines include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N- Dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, Triethylamine, trimethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyl Dihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, Ethyldioctylamine, ethyldinonylamine, ethyl didecylamine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylene Diamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-di Ethyldiphenylmethane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane, 1,2-di( 4-pyridyl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2- Di (4-pyridyloxy) ethane, di (2-pyridyl) ketone, 4,4'-dipyridyl sulfide, 4,4'-dipyridyl disulfide, 2,2'-dipyridylamine, 2 ,2'-dipicolylamine, bipyridine. Among these, diisopropyl aniline is preferable, and 2,6-diisopropyl aniline is especially more preferable.

Specific examples of the ammonium salt include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammoniumhydroxide, tetra-n-butylammoniumsalicylate and choline.

< Weak salt >

Salts which give rise to an acid less acidic than the acid arising from the acid generator (B) are sometimes referred to as "weak acid salts". "Acidity" can be expressed in terms of the acid dissociation constant, pKa, of an acid produced from a weak acid salt. Examples of the weak acid salt (D) include salts which generate acids whose pKa is usually -3 or more, preferably -1 to 7, more preferably 0 to 5.

Specific examples of weak acid salts include the following salts, salts of formula (D), and Japanese Patent Application Laid-Open No. 2012-229206, Japanese Patent Application Laid-Open No. 2012-6908, Japanese Patent Application Laid-Open No. 2012-72109, JP The salt of Unexamined-Japanese-Patent No. 2011-39502 and Unexamined-Japanese-Patent No. 2011-191745 is included, Preferably the salt of a formula (D) is included.

In the formula (D), R ^D1 and R ^D2 , in each case, are each independently a C ₁ to C ₁₂ hydrocarbon group, a C ₁ to C ₆ alkoxyl group, a C ₂ to C ₇ acyl group, C Represents a ₂ to C ₇ acyloxy group, a C ₂ to C ₇ alkoxycarbonyl group, a nitro group or a halogen atom,

m' and n' each independently represent the integer of 0-4.

Examples of the hydrocarbon group of R ^D1 and R ^D2 include any of an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and combinations thereof.

Examples of the aliphatic hydrocarbon group include an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, and a nonyl group.

The alicyclic hydrocarbon group is any one of a monocyclic or polycyclic hydrocarbon group and a saturated or unsaturated hydrocarbon group. Examples thereof include a cycloalkyl group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclononyl group, and a cyclododecyl group; an adamantyl group and a norbornyl group. The alicyclic hydrocarbon group is preferably a saturated hydrocarbon group.

Examples of the aromatic hydrocarbon group include a phenyl group, 1-naphthyl group, 2-naphthyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-propylphenyl group, 4-isopropylphenyl group, 4-butylphenyl group, 4-tert-butylphenyl group, 4-hexylphenyl group, 4-cyclohexylphenyl group, anthryl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, biphenyl group, and aryl groups such as a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group.

Examples of these combined groups include an alkyl-cycloalkyl group, a cycloalkyl-alkyl group, an aralkyl group (eg, phenylmethyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenyl-1-propyl group, 1- Phenyl-2-propyl group, 2-phenyl-2-propyl group, 3-phenyl-1-propyl group, 4-phenyl-1-butyl group, 5-phenyl-1-pentyl group, 6-phenyl-1-hexyl group practice) is included.

Examples of the alkoxyl group include a methoxy group and an ethoxy group.

Examples of the acyl group include an acetyl group, a propanoyl group, a benzoyl group, and a cyclohexanecarbonyl group.

Examples of the acyloxy group include a group in which an oxy group (-O-) is bonded to the acyl group.

Examples of the alkoxycarbonyl group include a group in which a carbonyl group (-CO-) is bonded to the alkoxy group.

Examples of the halogen atom are a fluorine atom, a chlorine atom and a bromine atom.

In formula (D), R ^D1 and R ^D2 in each case are each independently a C ₁ to C ₈ alkyl group, C ₃ to C ₁₀ cycloalkyl group, C ₁ to C ₆ alkoxyl group, C ₂ to Represents a C ₄ acyl group, a C ₂ to C ₄ acyloxy group, a C ₂ to C ₄ alkoxycarbonyl group, a nitro group or a halogen atom.

m' and n' are each independently preferably an integer of 0 to 3, more preferably an integer of 0 to 2, and still more preferably 0.

Specific examples of the formula (D) dml salt include the following compounds.

The salt of formula (D) can be prepared by the method described in "Tetrahedron Vol.45, No.19, p 6281-6296". Moreover, a commercially available compound can be used as a salt of Formula (D).

In the resist composition of the present invention, the content of a salt that generates an acid having a weaker acidity than the acid generated from the acid generator, for example, the salt of formula (D), is preferably based on the total solid content of the resist composition. It is 0.01-5 mass %, More preferably, it is 0.01-4 mass %, More preferably, it is 0.01-3 mass %.

< Other ingredients >

In addition, the resist composition may include other components (which are sometimes referred to as "other components (F)"). Examples of the other component (F) include various additives such as sensitizers, dissolution inhibitors, surfactants, stabilizers, and dyes, if necessary.

<Preparation of resist composition>

The resist composition of the present invention, if necessary, contains a resin (A), a compound (a), an acid generator (B), and a resin other than the resin (A), a solvent, a solvent (E), and other components ( It can be prepared by mixing F). It does not specifically limit in the mixing order. Mixing may be performed in any order. The mixing temperature may be adjusted to an appropriate temperature in the range of 10 to 40° C. according to the type of resin or the solubility of the resin in the solvent (E). The mixing time may be adjusted to an appropriate time in the range of 0.5 to 24 hours depending on the mixing temperature. The mixing means is not particularly limited. Agitated mixing may be employed.

After mixing the above components, the resist composition of the present application can be prepared by filtering the mixture through a filter having a pore diameter of approximately 0.003 to 0.2 mu m.

<Method for producing resist pattern>

The method for producing the resist pattern of the present invention comprises:

(1) a step of applying the resist composition of the present invention on a substrate;

(2) drying the applied composition to form a composition layer;

(3) a step of exposing the composition layer;

(4) heating the exposed composition layer; and

(5) The process of developing the heated composition layer is included.

Application of the resist composition onto the substrate can be carried out using a resist coating apparatus, such as a spin coater, which is typically known in the art of semiconductor microfabrication. Examples of the substrate include an inorganic substrate, such as a silicon wafer. Before apply|coating a resist composition, a board|substrate may be wash|cleaned, and you may form an organic antireflection film on a board|substrate using a commercially available antireflection composition.

The solvent is evaporated from the resist composition, and a composition layer from which the solvent is removed is formed. Drying of the applied composition layer may be done, for example, using a heating device, such as a hot plate (so-called pre-baking), or using a pressure reducing device or a combination thereof. Heating temperature becomes like this. Preferably it is within the range of 50-200 degreeC. The heating time is preferably 10 to 180 seconds. The pressure of the reduced pressure is preferably within the range of 1 to 1.0 × 10 ⁵ Pa.

The obtained composition layer is exposed using an exposure machine or an immersion exposure machine normally. The exposure is performed by radiation of a laser in the ultraviolet region, for example, a KrF excimer laser (wavelength 248 nm), an ArF excimer laser (wavelength 193 nm), an F ₂ excimer laser (wavelength 157 nm), a solid-state laser light source (YAG or semiconductor laser, etc.) ), wavelength-converting the laser beam from the laser beam, radiation of a harmonic laser beam in a deep ultraviolet region or a vacuum ultraviolet region, or radiation of an electron beam or EUV, etc., is usually carried out using various types of exposure machines. In this specification, irradiating these radiations is sometimes collectively referred to as exposure. Exposure is usually performed through a mask corresponding to a required pattern. When an electron beam is used as the exposure light source, it can be done by direct drawing without use of a mask.

After exposure, the composition layer is subjected to a heat treatment (so-called post-exposure bake) in order to accelerate the deprotection reaction. The heat treatment may be performed using a heating device such as a hot plate. Heating temperature is the range of 50-200 degreeC normally, Preferably it is the range of 70-150 degreeC.

Developing the heated composition layer is normally performed with a developing solution using a developing apparatus. Developing can be performed in the manner of a dip method, a puddle method, a spray method, or a dynamic dispensing method. Development temperature is 5-60 degreeC normally. The development time is usually 5 to 300 seconds.

The photoresist pattern obtained from the photoresist composition may be positive or negative depending on the choice of a suitable developer.

Development for obtaining a positive photoresist pattern is usually performed with an alkaline developer. The alkaline developer used may be any of various alkaline aqueous solutions used in this field. Usually, an aqueous solution of tetramethylammonium hydroxide or (2-hydroxyethyl)trimethylammonium hydroxide (commonly referred to as choline) is frequently used. Surfactant may be contained in alkaline developing solution.

After development, the formed resist pattern is preferably washed with ultrapure water, and the residue left on the resist layer or on the substrate is preferably removed.

Development for obtaining a negative photoresist pattern is usually performed with a developer containing an organic solvent. The organic solvent used may be any of various organic solvents used in this field, and examples of these include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents, such as N,N-dimethylacetamide; Contains aromatic hydrocarbon solvents such as anisole.

In the developer containing the organic solvent, the amount of the organic solvent in the developer is preferably 90% by mass to 100% by mass, more preferably 95% by mass to 100% by mass. The developer more preferably consists essentially of an organic solvent.

Especially, the developing solution containing an organic solvent, Preferably butyl acetate and/or 2-heptanone are included. In the developer containing the organic solvent, the total content of butyl acetate and 2-heptanone is preferably 50% by mass to 100% by mass in the developer, more preferably 90% by mass to 100% by mass in the developer. The developer more preferably consists essentially of butyl acetate and/or 2-heptanone.

The developing solution containing an organic solvent may contain surfactant. Moreover, the developing solution containing an organic solvent may also contain a trace amount of water|moisture content.

Developing with the developing solution containing an organic solvent can be complete|finished by substituting a developing solution with another solvent.

After development, the formed photoresist pattern is preferably washed with a rinsing solution. The rinsing solution is not limited as long as it does not damage the photoresist pattern. Examples of the rinsing solution include a solvent containing an organic solvent other than the above developer, such as an alcohol solvent or an ester solvent.

After cleaning, the residual rinse liquid left on the substrate or photoresist layer is preferably removed.

< Use >

The resist composition of the present invention is preferably useful for excimer laser lithography, such as lithography for KrF, ArF, electron beam (EB) exposure, or lithography for ultra-ultraviolet light (EUV) exposure, more preferably for electron beam (EB) exposure It is useful for lithography of , lithography for ArF excimer laser exposure, and lithography for ultra-ultraviolet light (EUV) exposure.

The resist composition of the present invention can be used in semiconductor microfabrication.

Examples

The present invention will be more specifically described by way of examples, which are not to be construed as limiting the scope of the present invention.

All percentages and parts expressing content or amount used in Examples and Comparative Examples are based on mass unless otherwise specified.

The weight average molecular weight is a value measured by gel permeation chromatography.

Column: TSKgel Multipore HXL-M x 3+guardcolumn (manufactured by Tosoh)

Eluent: tetrahydrofuran

Flow rate: 1.0 mL/min

Detector: RI Detector

Column temperature: 40℃

Injection volume: 100 μl

Standard material for calculating molecular weight: standard polystyrene (manufactured by Tosoh Corporation)

The structure of the compound was measured by mass spectrometry (liquid chromatography: type 1100, manufactured by Agilent, mass spectrometry: LC/MSD type, manufactured by Agilent). The peak value in mass spectrometry is referred to as “MASS”.

Example 1: Synthesis of a compound represented by formula (I-1)

In the reactor, 50 parts of the compound represented by the formula (I-1-a), 250 parts of chloroform, 33.9 parts of pyridine, 4.77 parts of dimethylaminopyridine, 152.76 parts of the compound represented by the formula (I-1-b) and the formula ( 82.26 parts of the compound represented by I-1-c) were added, and the mixture was stirred at 23°C for 5 hours. To the obtained reaction mixture, 1150 parts of chloroform was added, 314 parts of 5% hydrochloric acid were added, and the mixture was stirred at 23°C for 30 minutes. Thereafter, the mixture was allowed to stand and the organic layer was separated. 570 parts of ion-exchange water is added to the obtained organic layer, and it stirs at 23 degreeC for 30 minute(s), The organic layer is liquid-separated and it washes with water. Such a water washing operation was performed 6 times. The washed organic layer was concentrated, and purified by column chromatography [Kanto Chemical Co., Ltd., silica gel 60N spherical shape, neutral, 100-210 µm, solvent: a mixture of n-heptane and ethyl acetate (weight ratio 10/1)] By doing so, 153.82 parts of the compound represented by Formula (I-1) was obtained.

MS (mass spectrometry): 522.1 (molecular ion peak)

Example 2: Synthesis of a compound represented by formula (I-3)

In the reactor, 7.03 parts of the compound represented by the formula (I-3-a), 30 parts of chloroform, 3.39 parts of pyridine, 0.48 parts of dimethylaminopyridine, 15.28 parts of the compound represented by the formula (I-1-b) and the formula ( 8.23 parts of the compound represented by I-1-c) were added, and the mixture was stirred at 23° C. for 5 hours. Then, to the obtained reaction mixture, 150 parts of chloroform was added, 32 parts of 5% hydrochloric acid was added, and the said mixture was stirred at 23 degreeC for 30 minutes. Thereafter, the mixture was allowed to stand and the organic layer was separated. 70 parts of ion-exchange water is added to the obtained organic layer, the said obtained mixture is stirred at 23 degreeC for 30 minutes, the organic layer is liquid-separated and it washes with water. Such a water washing operation was performed 5 times. The washed organic layer was concentrated and purified by column chromatography [manufactured by Kanto Chemicals, silica gel 60N spherical shape, neutral, 100-210 µm, solvent: a mixture of n-heptane and ethyl acetate (weight ratio 10/1)], the formula ( 12.48 parts of the compound represented by I-3) were obtained.

MS (mass spectrometry): 574.2 (molecular ion peak)

Example 3: Synthesis of the compound represented by formula (I-4)

In the reactor, 4.45 parts of the compound represented by the formula (I-4-a), 30 parts of chloroform, 3.39 parts of pyridine, 0.48 parts of dimethylaminopyridine, 15.28 parts of the compound represented by the formula (I-1-b) and the formula ( 8.23 parts of the compound represented by I-1-c) were added, and the mixture was stirred at 23° C. for 5 hours. Then, to the obtained reaction mixture, 150 parts of chloroform was added, 32 parts of 5% hydrochloric acid was added, and the said mixture was stirred at 23 degreeC for 30 minutes. Thereafter, the mixture was allowed to stand and the organic layer was separated. 70 parts of ion-exchange water is added to the obtained organic layer, the obtained mixture is stirred at 23 degreeC for 30 minutes, the organic layer is liquid-separated and it washes with water. Such a water washing operation was performed 5 times. The washed organic layer was concentrated and purified by column chromatography [Kanto Chemical Co., Ltd., silica gel 60N spherical shape, neutral, 100-210 µm, solvent: a mixture of n-heptane and ethyl acetate (weight ratio 10/1)], the formula 6.88 parts of the compound represented by (I-4) was obtained.

MS (mass spectrometry): 508.1 (molecular ion peak)

Synthesis Example 1: Synthesis of salt represented by formula (B1-5)

In a reactor, 50.49 parts of the salt represented by Formula (B1-5-a) and 252.44 parts of chloroform were put, and it stirred at 23 degreeC for 30 minutes. Thereafter, 16.27 parts of the compound represented by the formula (B1-5-b) was added dropwise, and the resulting mixture was stirred at 23° C. for 1 hour to obtain a solution containing a salt represented by the formula (B1-5-c). To the obtained solution, 48.80 parts of the salt represented by the formula (B1-5-d) and 84.15 parts of ion-exchanged water were added, and the resulting mixture was stirred at 23°C for 12 hours. The chloroform layer was taken out from the obtained reaction liquid which has two layers, 84.15 parts of ion-exchange water was added after that, and it washed with water. This washing operation was repeated 5 times. To the washed chloroform layer, 3.88 parts of activated carbon was added, and the resulting mixture was stirred and filtered. The filtrate taken out was concentrated, 125.87 parts of acetonitrile was added after that, and the obtained mixture was stirred and concentrated. To the obtained residue, 20.62 parts of acetonitrile and 309.30 parts of tert-butylmethyl ether were added, followed by stirring at 23°C for 30 minutes. Thereafter, the supernatant was removed and the residue was concentrated. To the concentrated residue, 200 parts of n-heptane was added, and the resulting mixture was stirred at 23° C. for 30 minutes and filtered to obtain 61.54 parts of a salt represented by the formula (B1-5).

MASS(ESI(+)Spectrum) : M ⁺ 375.2

MASS(ESI(-)Spectrum) : M ^- 339.1

Synthesis Example 2: Synthesis of salt represented by formula (B1-21)

The compound represented by the formula (B1-21-b) was produced by the method described in Japanese Patent Laid-Open No. 2008-209917.

In a reactor, 30.00 parts of the compound represented by the formula (B1-21-b), 35.50 parts of the salt represented by the formula (B1-21-a), 100 parts of chloroform and 50 parts of ion-exchanged water are put, and the mixture is placed at 23° C. for 15 hours. stirred. In the obtained reaction mixture having two layers, the chloroform layer was separated. 30 parts of ion-exchanged water was added to the said chloroform layer, and it washed with water. This washing operation was repeated 5 times. The washed layer is concentrated, and then 100 parts of tert-butylmethyl ether is added to the obtained residue, and the mixture is stirred at 23°C for 30 minutes. By filtration of the obtained mixture, 48.57 parts of salts represented by Formula (B1-21-c) were obtained.

In a reactor, 20.00 parts of the salt represented by the formula (B1-21-c), 2.84 parts of the compound represented by the formula (B1-21-d) and 250 parts of monochlorobenzene were put, and the mixture was stirred at 23° C. for 30 minutes. To the obtained mixture, 0.21 part of copper (II) dibenzoate was added, and the obtained mixture was stirred at 100 degreeC for 1 hour. The obtained reaction mixture is concentrated, and then 200 parts of chloroform and 50 parts of ion-exchanged water are added to the obtained residue, and the obtained mixture is stirred at 23 degreeC for 30 minutes, and the organic layer is separated and washed with water. 50 parts of ion-exchanged water is added to the obtained organic layer, the obtained mixture is stirred at 23 degreeC for 30 minutes, and the organic layer is separated and washed with water. This washing operation was repeated 5 times. The obtained organic layer was concentrated, and then the obtained residue was dissolved in 53.51 parts of acetonitrile. Thereafter, the mixture was concentrated, 113.05 parts of tert-butylmethyl ether was added, and the resulting mixture was stirred and filtered to obtain 10.47 parts of a salt represented by the formula (B1-21).

MASS(ESI(+)Spectrum) : M ⁺ 237.1

MASS(ESI(-)Spectrum) : M ^- 339.1

Synthesis Example 3: Synthesis of salt represented by formula (B1-22)

In a reactor, 11.26 parts of the salt represented by the formula (B1-21-a), 10 parts of the compound represented by the formula (B1-22-b), 50 parts of chloroform and 25 parts of ion-exchanged water were put, and the mixture was placed at 23° C. for 15 hours. stirred. The resulting reaction mixture having two layers was separated from the chloroform layer. 15 parts of ion-exchanged water was added to the said chloroform layer, and it washed with water. This washing operation was repeated 5 times. Thereafter, the layer washed with water is concentrated, and 50 parts of tert-butylmethyl ether is added to the obtained residue, and the resulting mixture is stirred at 23° C. for 30 minutes. 11.75 parts of salts represented by Formula (B1-22-c) were obtained by filtering the obtained mixture.

In a reactor, 11.71 parts of the salt represented by the formula (B1-22-c), 1.70 parts of the compound represented by the formula (B1-21-d), and 46.84 parts of monochlorobenzene were put, and the mixture was stirred at 23° C. for 30 minutes. To the obtained mixture, 0.12 part of copper (II) dibenzoate was added, and the obtained mixture was stirred at 100 degreeC for 30 minute(s). The reaction mixture is concentrated, and 50 parts of chloroform and 12.50 parts of ion-exchanged water are added to the residue obtained after that, and the resulting mixture is stirred at 23°C for 30 minutes, and the organic layer is separated and washed with water. 12.50 parts of ion-exchanged water is added to the obtained organic layer, and it stirs at 23 degreeC for 30 minutes, The organic layer is separated and washed with water. This washing operation was repeated 8 times. Thereafter, the mixture was concentrated, 50 parts of tert-butylmethyl ether was added, and the resulting mixture was stirred and filtered to obtain 6.84 parts of a salt represented by the formula (B1-22).

MASS(ESI(+)Spectrum) : M ⁺ 237.1

MASS(ESI(-)Spectrum) : M ^- 323.0

Example of resin synthesis

The monomers used for the synthesis examples of the resin are shown below. These monomers are referred to as "monomer (X)", where "(X)" is a symbol of the formula indicating the structure of each monomer.

Synthesis Example 4: Synthesis of Resin A1

Monomer (a1-1-3), Monomer (a1-2-9), Monomer (a2-1-3) and Monomer (a3-4-2), Monomer (a1-1-3), Monomer (a1- 2-9), monomer (a2-1-3), and monomer (a3-4-2) are mixed with each other so that the molar ratio of the monomer (a3-4-2) is 45:14:2.5:38.5, and propylene in an amount equal to 1.5 times by mass of the total amount of the monomer Glycol monomethyl ether acetate is added to obtain a solution. To this solution, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in amounts of 1 mol% and 3 mol%, respectively, based on the total amount of the monomers, and the reaction mixture was 73 It was heated at ℃ for about 5 hours. Then, the obtained reaction mixture is poured into the mixture of a large amount of methanol and water, and resin is precipitated. The obtained resin is filtered. The obtained resin is dissolved in another propylene glycol monomethyl ether acetate to obtain a solution, and the solution is poured into a large amount of a mixture of methanol and water to precipitate the resin. The obtained resin is filtered. This operation was repeated twice to obtain a copolymer having a weight average molecular weight of about 7600 in a yield of 68%. The said resin which has a structural unit of the following formula is called resin A1.

Example 4: Synthesis of Resin X1

Using the monomer (I-1), propylene glycol monomethyl ether acetate in an amount equal to 1.5 times by mass of the total amount of the monomer is added to obtain a solution. To the solution, 0.7 mol% and 2.1 mol% of azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile), respectively, based on the total amount of monomers, as initiators, were added, and the resulting mixture was heated to about 75°C. Heated for 5 hours. Then, the obtained reaction mixture is poured into the liquid mixture of a large amount of methanol and water, and resin is precipitated. The obtained resin is filtered. The resin thus obtained is dissolved in another propylene glycol monomethyl ether acetate to obtain a solution, and the solution is poured into a mixture of methanol and water to precipitate the resin. The obtained resin is filtered. This operation was repeated three times to obtain a copolymer having a weight average molecular weight of about 14000 in a yield of 68%. The said resin which has a structural unit of the following formula is called resin X1.

Example 5: Synthesis of Resin X2

Using the monomer (I-1), propylene glycol monomethyl ether acetate in an amount equal to 1.5 mass times the total amount of the monomer is added to obtain a solution. To the solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile), respectively, based on the total amount of monomers as initiators were added, and the resulting mixture was heated to about 75°C. Heated for 5 hours. Then, the obtained reaction mixture is poured into the liquid mixture of a large amount of methanol and water, and resin is precipitated. The resin is filtered. The resin thus obtained is dissolved in another propylene glycol monomethyl ether acetate to obtain a solution, and the solution is poured into a mixture of methanol and water to precipitate the resin. The obtained resin is filtered. This operation was repeated three times to obtain a copolymer having a weight average molecular weight of about 7800 in a yield of 65%. The said resin which has the structural unit of the following formula is called resin X2.

Example 6: Synthesis of Resin X3

Monomer (I-1) and monomer (a4-0-12) are mixed with each other so that a molar ratio of [monomer (I-1)]/[monomer (a4-0-12)] = 50/50, and all monomers A solution is obtained by adding propylene glycol monomethyl ether acetate in an amount equal to 1.5 mass times the amount. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added to this solution, respectively, based on the total amount of monomers, and the resulting mixture was heated to about 75°C. Heated for 5 hours. Then, the obtained reaction mixture is poured into the liquid mixture of a large amount of methanol and water, and resin is precipitated. The obtained resin is filtered. The resin thus obtained is dissolved in another propylene glycol monomethyl ether acetate to obtain a solution, and the solution is poured into a mixture of methanol and water (methanol/ion-exchanged water = 4/1) to precipitate the resin. The obtained resin is filtered. This operation was repeated three times to obtain a copolymer having a weight average molecular weight of about 8000 in a yield of 82%. The said resin which has a structural unit of the following formula is called resin X3.

Example 7: Synthesis of Resin X4

Monomer (I-1) and monomer (a5-1-1) are mixed with each other so that the molar ratio of [monomer (I-1)]/[monomer (a5-1-1)] = 50/50, and all monomers A solution is obtained by adding propylene glycol monomethyl ether acetate in an amount equal to 1.5 mass times the amount. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added to this solution, respectively, based on the total amount of monomers, and the resulting mixture was heated to about 75°C. Heated for 5 hours. Then, the obtained reaction mixture is poured into the liquid mixture of a large amount of methanol and water, and resin is precipitated. The obtained resin is filtered. The obtained resin is dissolved in another propylene glycol monomethyl ether acetate to obtain a solution, and the solution is poured into a mixture of methanol and water (methanol/ion-exchanged water = 4/1) to precipitate the resin. The obtained resin is filtered. This operation was repeated three times to obtain a copolymer having a weight average molecular weight of about 7600 in a yield of 88%. The said resin which has the structural unit of the following formula is called resin X4.

Example 8: Synthesis of Resin X5

Using the monomer (I-3), propylene glycol monomethyl ether acetate in an amount equal to 1.5 mass times the total amount of the monomer is added to obtain a solution. To the solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile), respectively, based on the total amount of monomers as initiators were added, and the resulting mixture was heated to about 75°C. Heated for 5 hours. The obtained reaction mixture is poured into a liquid mixture of a large amount of methanol and water to precipitate a resin. The obtained resin is filtered. The obtained resin is dissolved in another propylene glycol monomethyl ether acetate to obtain a solution, and the solution is poured into a mixture of methanol and water (methanol/ion-exchanged water = 4/1) to precipitate the resin. The obtained resin is filtered. This operation was repeated three times to obtain a copolymer having a weight average molecular weight of about 8600 in a yield of 60%. The said resin which has the structural unit of the following formula is called resin X5.

Example 9: Synthesis of Resin X6

Using the monomer (I-4), propylene glycol monomethyl ether acetate 1.5 mass times the total amount of the monomer was added to obtain a solution. To the solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile), respectively, based on the total amount of monomers as initiators were added, and the resulting mixture was heated to about 75°C. Heated for 5 hours. Then, the obtained reaction mixture is poured into the liquid mixture of a large amount of methanol and water, and resin is precipitated. The obtained resin is filtered. The obtained resin is dissolved in another propylene glycol monomethyl ether acetate to obtain a solution, and the solution is poured into a mixture of methanol and water (methanol/ion-exchanged water = 4/1) to precipitate the resin. The obtained resin is filtered. This operation was repeated three times to obtain a copolymer having a weight average molecular weight of about 7800 in a yield of 75%. The said resin which has the structural unit of the following formula is called resin X6.

Synthesis Example 5: Synthesis of Resin XX1

Monomer (a4-1-7) and monomer (IX-1) are mixed with each other so that the molar ratio of [monomer (a4-1-7)]/[monomer (IX-1)] = 90/10, and all monomers A solution is obtained by adding propylene glycol monomethyl ether acetate in an amount equal to 1.5 mass times the amount. To this solution, 0.9 mol% and 2.7 mol% of azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile), respectively, based on the total amount of monomers as initiators were added, and these were added at 75°C for about 5 hours. heated. Then, the obtained reaction mixture is poured into the liquid mixture of a large amount of methanol and water, and resin is precipitated. The obtained resin is filtered. The obtained resin is dissolved in another propylene glycol monomethyl ether acetate to obtain a solution, and the solution is poured into a mixture of methanol and water (methanol/ion-exchanged water = 4/1) to precipitate the resin. The obtained resin is filtered. This operation was repeated three times to obtain a copolymer having a weight average molecular weight of about 13000 in a yield of 80%. The said resin which has the structural unit of the following formula is called resin XX1.

(Preparation of resist composition)

A resist composition was prepared by mixing and dissolving each component shown in Table 1, followed by filtration through a fluororesin filter having a pore diameter of 0.2 mu m.

< Resin >

A1, X1 to X6, XX1: Resin A1 prepared by synthesis of resin, resin X1 to resin X6, resin XX1

<Salt (a)>

B1-5: salt represented by formula (B1-5)

B1-21: salt represented by formula (B1-21)

B1-22: salt represented by formula (B1-22)

< Weak acid intramolecular salt (D) >

D1: The following salt manufactured by Tokyo Kasei Industrial Co., Ltd.

< Solvent of resist composition >

265 parts of propylene glycol monomethyl ether acetate

Propylene glycol monomethyl ether 20 parts

2-heptanone 20 parts

γ-butyrolactone 3.5 parts

(Production of negative resist pattern)

On a 12-inch silicon wafer, an organic antireflection film composition ("ARC-29", manufactured by Nissan Chemical Co., Ltd.) was coated and baked at 205°C for 60 seconds to form an organic antireflection film with a thickness of 78 nm do.

To one of the processed wafers, one of the resist compositions is then applied by spin coating in such a way that the film thickness after drying (pre-baking) becomes 100 nm.

Thereafter, the obtained wafer was prebaked on a direct hot plate at the temperature given in the "PB" column of Table 1 for 60 seconds.

Thereafter, the layer on the wafer on which the resist layer was formed was formed using an ArF excimer laser stepper for immersion lithography (XT: 1900Gi; manufactured by ASML, NA = 1.35, Annular σ _out = 0.85 σ _in = 0.65 XY-pol.) , through a mask for forming a trench pattern (pitch 120 nm/trench width 40 nm), by changing the exposure amount stepwise, was exposed.

After exposure, a post-exposure bake is performed for 60 seconds at the temperature given in the "PEB" column of Table 1.

Next, development was performed with butyl acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) by a dynamic dispensing method at 23 DEG C for 20 seconds to prepare a negative resist pattern.

The effective sensitivity is expressed by the exposure amount at which a resist pattern having a trench width of 40 nm is obtained.

( Line Edge Roughness Evaluation (LER) )

Each wall surface of the resist pattern after the lithography step was observed using a scanning electron microscope.

The mark "○" is given when the unevenness of the wall surface has a roughness width of 3 nm or less.

The mark "x" is given when the unevenness of the wall surface has a roughness width of more than 3 nm.

Table 2 shows the results. The number in parentheses means the value of the roughness width (nm).

(Evaluation of defects)

ArF excimer laser stepper for immersion lithography [XT: 1900 Gi; manufactured by ASML, NA = 1.35, Annular σ _out = 0.85 σ _in = 0.65 XY-pol.] and a mask for forming a 1:1 line-and-space pattern (pitch 80 nm), the layer was subjected to an exposure dose A negative resist pattern was produced by performing the same operation as above except for exposure.

After that, the defect inspection apparatus [KLA-2360; KLA Tenchol] was used to measure the number of defects (pieces). The results are shown in Table 2.

In Reference Example 1, Comparative Composition 1 was not stored at 30°C for 3 weeks, but was evaluated immediately after production.

The compounds of the present invention are useful as resins for resist compositions. A resist composition comprising the resin may exhibit storage stability providing low line edge roughness (LER) and defect-free to resist patterns. Therefore, the resist composition can be used for microfabrication of semiconductors.

Claims (9)

The compound represented by Formula (I).

[Here, R ¹ represents a C ₁ to C ₈ fluorinated alkyl group,
R ² represents a group having an optionally substituted C ₅ to C ₁₈ alicyclic hydrocarbon group,
R ³ represents a hydrogen atom, a halogen atom, or a C ₁ to C ₆ alkyl group which may have a fluorine atom, and
A ¹ represents a single bond or an optionally substituted C ₁ to C ₁₀ saturated hydrocarbon group, and the methylene group contained in the saturated hydrocarbon group may be substituted with an oxygen atom or a carbonyl group.] The method of claim 1,
The compound wherein the alicyclic hydrocarbon group is an unsubstituted alicyclic hydrocarbon group. The method of claim 1,
R ² is a cyclohexyl group, a cyclopentyl group, a norbornyl group, or an adamantyl group. A resin having a structural unit derived from the compound according to claim 1 . 5. The method of claim 4,
Resin which contains 50 mol% or more of the structural unit derived from the compound represented by Formula (I). 5. The method of claim 4,
Resin comprised by the structural unit derived from the compound represented by Formula (I). A resist composition comprising:
The resin according to claim 4,
a resin having an acid labile group, which is a group having a leaving group, which is released by contact with an acid to form a hydroxy group or a carboxy group, and
A resist composition comprising an acid generator, which is a compound that generates an acid by radiation. A method for producing a resist pattern comprising steps (1) to (5):
(1) a step of applying the resist composition according to claim 7 on a substrate;
(2) drying the applied composition to form a composition layer;
(3) a step of exposing the composition layer;
(4) heating the exposed composition layer; and
(5) A step of developing the heated composition layer. delete